Navigate to Community section

15 American Rabbis You Haven’t Heard Of, But Should

These Jewish leaders’ influence has been felt around the country, in every denomination, even if you don’t know them by name

Yair Rosenberg
September 15, 2014
Top row, left to right: Analia Bortz, Ethan Linden, Rachel Isaacs, Darby Leigh, James Ponet. Middle row, left to right: David Wolkenfeld, Barry Dov Katz, Debra Nesselson, Aryeh Klapper. Bottom row, left to right: Jeremy Wieder, Shnayer Leiman, Elana Stein-Hain, Brian Zimmerman, Jason Rubenstein.(Photoillustration Tablet Magazine)
Top row, left to right: Analia Bortz, Ethan Linden, Rachel Isaacs, Darby Leigh, James Ponet. Middle row, left to right: David Wolkenfeld, Barry Dov Katz, Debra Nesselson, Aryeh Klapper. Bottom row, left to right: Jeremy Wieder, Shnayer Leiman, Elana Stein-Hain, Brian Zimmerman, Jason Rubenstein.(Photoillustration Tablet Magazine)

Last February, Newsweek announced the end of its yearly listing of “America’s top rabbis.” First compiled in 2007, the list offered a helpful snapshot of the country’s Jewish leadership each year but also drew criticism for its inevitable omissions and tendency to confuse media attention for spiritual impact when selecting its subjects.

This is not that kind of list.

Our showcase of American rabbis is not a ranking, and it makes no attempt to be comprehensive. Instead, our aim is to highlight the work of Jewish leaders and teachers who don’t typically command the national spotlight—none of them ever appeared on Newsweek’s list—but whose influence has been profound. Some are longstanding rabbis who have done their work outside major organizations and synagogues, or just beyond the reach of the media; others are rising young leaders whom the broader Jewish world has yet to discover.

These are rabbis you haven’t heard of, but should. They are the mentors whose synagogues and teachings are well worth exploring during this year’s High Holidays season.

We do not think we have left off many individuals who ought to be on this list—we know we have. Our selection—published in alphabetical order—is not meant to be exhaustive, but rather suggestive of the incompleteness of traditional lists of this kind. Which is why we encourage you to add your own nominations in the comments and turn this page into a testament to the unheralded heroes of American Jewish life—hopefully spurring others to discover them, too.

To jump directly to each rabbi’s entry, click on the names below.


Analia Bortz
Congregation Or Hadash | Sandy Springs, Ga.
Doctor, scholar, cantor, rabbi

Analia Bortz has earned a medical degree, worked at Hadassah Hospital in Jerusalem, directed a cantorial school, lectured on bioethics at multiple universities, and published scholarship on the philosophical thought of Maimonides, Emmanuel Levinas, and Martin Buber.

And that was all before she came to the United States and built her own synagogue.

One of the first female rabbis ordained in South America, Bortz completed medical school at the University of Buenos Aires, did graduate work in radiology in Israel, and then returned to Argentina to receive her ordination at the Seminario Rabínico Latinoamericano in 1994. She taught bioethics and Jewish philosophy at the University of Valparaiso in Chile—where she also ran the local Talmud Torah and cantorial school—before moving to Atlanta in 2000.

In 2003, Bortz and her husband, Rabbi Mario Karpuj, founded the Conservative Congregation Or Hadash, to which they brought their expansive erudition and a passion for music drawn from the Latin American Jewish tradition. The synagogue started with 50 families. It now has 400. Many of Or Hadash’s congregants hail from outside the United States, and Bortz’s home on Passover has been described as a “United Nations,” filled with Jews of all nationalities and backgrounds. (It helps that Bortz speaks five languages.)

Bortz also continues to draw on her medical background in her pastoral work. She founded Seeds of Hope, a support group for women struggling with infertility. And when Hurricane Katrina hit, Bortz departed to offer medical assistance to the victims in New Orleans—and only then rushed back to Atlanta to officiate at a wedding.

Shlomo Einhorn
Yavneh Hebrew Academy | Los Angeles, Calif.
The Orthodox Union’s synagogue guru

Shlomo Einhorn is a rock star rabbi. And it’s not just because he has his own album. It’s because the 35-year-old is one of the most successful synagogue rabbis in America and the Orthodox Union’s go-to person for revitalizing religious life around the country.

When Einhorn arrived at New York’s West Side Institutional Synagogue in 2005, the place was practically deserted. Shabbat morning services boasted an attendance of 12. But seven years later, Einhorn was drawing over 400 people each week and had increased synagogue membership by 70 percent. He did it with out-of-the-box events with flashy titles, like an annual “Rock ‘n’ Roll Shabbaton” featuring actual performing artists—including Roger Daltrey, the frontman of The Who. In addition, Einhorn designed educational programs that integrated elements of popular psychology and delivered sermons that were almost as likely to cite Led Zeppelin or Bob Dylan as they were to quote the Talmud or Hasidic masters.

Einhorn’s work was so successful that in 2010 the Orthodox Union gave him his own think tank to craft programming for other synagogues across America. Want to grow your membership? Run a successful Hanukkah event? Spice up your shul’s Shabbat? Einhorn has a program for that.

In 2012, Einhorn moved back to his hometown of Los Angeles to serve as dean of Yavneh Hebrew Academy, an elite Modern Orthodox prep school, and as the rabbi of its congregation. Since then, he’s embarked on a popular Los Angeles lecture tour covering the history of Orthodox Judaism and launched a sermon series on repentance that continues through the High Holidays.

Rachel Isaacs
Congregation Beth Israel, Colby College | Waterville, Maine
Building campus and community in Maine

When Rachel Isaacs was ordained at the Jewish Theological Seminary in May 2011, she made headlines as the first openly gay rabbi to graduate from the Conservative institution. But three years later, she is making waves not just for what she represents, but for the energy and inspiration she has injected into the Jewish community of Maine.

After her ordination, Isaacs assumed the pulpit of Congregation Beth Israel in Waterville—a historic synagogue community founded over a century ago, with an aging and diminishing population. Under Isaacs’ leadership, its membership is now growing again. And Beth Israel is not the only Jewish institution experiencing a revival on her watch.

When Isaacs arrived at Colby College as its Jewish chaplain in late 2011, the number of students who regularly came to Hillel could be counted on one hand. There were weekly Shabbat candle-lightings and a couple holiday parties, but not much else by way of Jewish life. Isaacs challenged the students to run monthly Shabbat dinners, which soon became weekly, and things snowballed from there. Today, Colby Hillel attracts dozens of students and is, in the words of the college’s dean of students, “one of the most dynamic and active student groups on campus.”

Isaacs herself teaches at Hillel everything from Talmud to the fundamentals of Zionist thought, offering students a more personal and informal avenue to Jewish learning than typically found in an academic setting. Over the last year, she has helped organize an intercollegiate shabbaton and Maine’s first Conference for Jewish Life, featuring pluralistic learning, academic lectures, and a klezmer band.

If there’s one thing Isaacs hopes her pupils take away from their experience, it’s that “this 5,000-year-old tradition is theirs—it’s theirs to learn, it’s theirs to engage in, it’s theirs to change, it’s theirs to put into action.”

Barry Dov Katz
Congregation Adath Israel | Riverdale, N.Y.
Reviving Conservative Judaism in the heart of Modern Orthodoxy

Whether it’s stirring controversy over women wearing tefillin or debating women being ordained as rabbis, the Jewish community of Riverdale, N.Y., is often in the headlines—that is, the Orthodox community. While the area has many large Orthodox congregations and educational institutions, it is not particularly renowned for its non-Orthodox life. But under Barry Dov Katz, the Conservative synagogue Adath Israel of Riverdale has experienced something of a renaissance.

When Katz arrived in 1998 with his wife Shoshi, the congregation was graying, with few young couples to replenish the ranks. Today, as one longtime synagogue member puts it, “it’s impossible to navigate around the stroller-filled coat room in the shul.” This revival is due in large part to Katz’s ability to connect with Jews of all ages and backgrounds—not least the neighborhood’s Orthodox community. He has taught safrut (the writing of sacred religious texts) to third- and fourth-graders at the Modern Orthodox SAR Academy. And he runs joint Israel-related programming with a local Orthodox synagogue, Young Israel Ohab Zedek. At Adath Israel, when not crafting creative offerings like outdoor summer Shabbat davening or performative Torah readings, he mentors rabbinical students from the Jewish Theological Seminary as synagogue interns, many of whom now occupy Conservative pulpits across America.

It’s an approach that has won him not only congregants, but respect beyond his community. As one local Orthodox rabbi put it, the secret to Katz’s success is “no fancy thrills, just an outstanding, hard-working, talented rabbi with great vision and mentschlichkeit.”

Aryeh Klapper
Center for Modern Torah Leadership | Sharon, Mass.
Fostering an Orthodoxy unafraid of the secular university

Some rabbis aspire to have their own congregation. Others hope to teach in a Jewish day school or rabbinical seminary. Aryeh Klapper’s preferred pulpit, however, was the college campus. When many educators in the Orthodox community eyed secular universities with suspicion and directed their students to religious institutions like Yeshiva University, Klapper—himself a graduate of Y.U.—set out to minister to those who chose to go elsewhere.

He taught at several colleges on the east coast, from Brandeis to Yale to Cornell, before serving as the Orthodox rabbinic adviser at Harvard Hillel for a decade. He launched a co-ed Summer Beit Midrash program for students across America, which is now entering its 18th year. And with his wife Deborah he has fostered scores of prominent Jewish rabbis, educators, and lay leaders—many of whom have followed in his footsteps as campus rabbis at places like Princeton, Yale, and the University of Pennsylvania.

Central to Klapper’s approach, and the Center for Modern Torah Leadership institute that he runs, is the belief that the “intellectual and moral challenges of modernity” present “spiritual opportunities” for religious believers, rather than obstacles. In other words, Torah is not undermined by modern thought, but enhanced by it. Thus, in his lectures, Klapper relates Jewish tradition substantively to labor laws, human rights, torture, and many other contemporary public policy issues. He’s explained the ostensibly arcane meaning of biblical animal sacrifice with reference to academic research on the appeal of paganism. And he’s spent a summer with his students constructing a Jewish legal ethic of investigative journalism, with input from the former ombudsman of the Boston Globe and George Washington Law School’s Jeffrey Rosen, among others.

This year, Klapper stepped down as instructor of rabbinics at the pluralistic Gann Academy in Waltham, Mass., to focus full-time on publishing and teaching across the country.

Darby Leigh
Congregation Kerem Shalom | Concord, Mass.
“I may not hear very well, but I really know how to listen”

In August 2013, Darby Leigh became only the second deaf rabbi to lead a hearing congregation in the United States when he assumed the pulpit of the Kerem Shalom synagogue in Concord, Mass.

A religion major in college who graduated summa cum laude and Phi Beta Kappa, Leigh originally thought there was no place in the rabbinate for someone without the ability to hear. “I knew I wanted to become a rabbi,” he said. “I wanted to sing and dance and pray, to engage people in this search for truth. But I pushed the thought away. A deaf rabbi?” He toured for four years as an actor for the National Theater of the Deaf. But with the encouragement of mentors, he enrolled in the Reconstructionist Rabbinical College, where he mastered Hebrew and was ordained in 2008. He then served as assistant rabbi at Congregation B’nai Keshet in Montclair, N.J., before assuming his position at Kerem Shalom last summer.

Today, the 40-year-old rabbi serves the 250-member congregation and the broader Jewish community in myriad ways, from blowing shofar on Rosh Hashanah to translating traditional prayers like the Shema into ASL. He has been known to draft his sermons while listening to heavy metal, of which he is a lifelong fan. (He has even appeared on stage alongside his childhood idols Twisted Sister and Jane’s Addiction.)

“I may not hear very well,” he is fond of saying, “but I really know how to listen.”

Shnayer Leiman
Brooklyn College / Yeshiva University | Queens, N.Y.
The Sherlock Holmes of Jewish history

The Sherlock Holmes of Jewish history lives in Queens. Among other exploits, Shnayer Leiman has exposed as a forgery a letter of Reform Judaism forerunner Moses Mendelssohn that sold at auction for over $5,000; shown how the popularizer of the Golem legend lifted from Sir Arthur Conan Doyle; revealed a famous rabbi to have likely been a secret follower of the 17th-century false messiah Shabbetai Tzvi; and revived the stories of forgotten female Jewish writers and Torah teachers.

Leiman received his doctorate at the University of Pennsylvania in 1970—where he literally wrote the book on The Canonization of Hebrew Scripture—and his rabbinic ordination from the Mirrer Yeshiva in Brooklyn. As a student, he helped build Yavneh, the national Orthodox Jewish student movement on campus. As a scholar, he has taught thousands of pupils, most recently at Yeshiva University and Brooklyn College, and previously at Harvard, Oxford, Hebrew University, and Yale, where he directed the school’s programs in Jewish studies.

Leiman’s work ranges from the minutiae of biblical scholarship to Jewish medical ethics to traditional Judaism’s encounter with modernity, a rare feat in the era of academic specialization. Not content for such learning to remain in the Ivory Tower, Leiman has long endeavored to make it accessible to the broader Jewish community. For over 40 years, he has opened his home for a biweekly Sabbath lecture that regularly draws so many attendees, they sometimes have to sit on the porch. Leiman leads summer tours across the historic Jewish communities of Europe and also maintains a website that offers much of his scholarship free of charge, as well as some of the contents of his personal library of over 30,000 books and 70,000 other historical artifacts.

Ethan Linden
Congregation Shir Chadash | New Orleans, La.
The next generation of Conservative leadership

Ethan Linden often comes across as the class clown who somehow ended up giving the sermon. The rabbi of Congregation Shir Chadash in New Orleans, he is known for his goofball sense of humor and self-deprecating demeanor. But when he arrived in 2009 to take up his position, he faced the very serious task of helping rebuild a Jewish community that had been ravaged by Hurricane Katrina. Five years later, the Conservative congregation he leads is thriving, drawing singles, families, and the elderly, with Linden and his wife Liba at its center.

When many young leaders raised in the Conservative movement were departing for independent minyanim and post-denominational institutions, Linden opted to stay. He began his Jewish communal career as the assistant director of Camp Ramah in New England, was ordained in 2007, and went on to serve as the Conservative rabbinic adviser at Harvard Hillel. There he endeared himself to students with his ability to address serious religious questions, but not take himself too seriously. (Many still recall the time he ran a game show about the Jewish legal intricacies of “kosher sex.”)

At a moment when the future of Conservative Judaism is often called into question, Linden represents a new generation that hopes to reshape and restore it. When one noted Conservative rabbi responded to the recent Pew report on American Jewry—which revealed the denomination’s tremendous attrition rate—by saying “our house is on fire,” Linden wrote, “I’m not leaving, because though much has burned, there is much yet to be saved.”

Debra Nesselson
Highland Park, Ill.
A rabbi without a pulpit for Jews without a shul

A typical list of influential rabbis will naturally represent those who are affiliated with Jewish communal institutions like synagogues and Hillel Houses. Most spiritual leaders, after all, aim to serve those Jews who show up. Debra Nesselson, however, serves those who don’t.

Nesselson is a freelance rabbi—a shepherd of those Jews who belong to no flock, having chosen not to affiliate with traditional Jewish institutions. But she didn’t start out this way. For a decade, Nesselson served as a rabbi at the 300-family Reform Congregation B’nai Torah in Highland Park, Chicago. But in 2011, she stepped down from her pulpit to pursue a different demographic: the growing portion of American Jewry that has been dropping out of organized Jewish life. (The 2011 Jewish Community Study of New York, for instance, found that only 44 percent of households in the country’s largest Jewish population were affiliated with a synagogue, with that number dropping to 29 percent among non-Orthodox young Jews living outside the home.)

Today, Nesselson travels across the country performing bar and bat mitzvahs, weddings, funerals, and other religious services for these Jews. And every year, she conducts High Holiday services at the Highland Park Community House for those uncomfortable with an institutional setting. “Many ‘unaffiliated’ Jews are actually quite affiliated. There are myriads of ways to be Jewish,” she writes. “Among the unaffiliated are many Jews for whom their Jewishness remains an integral part of who they are.”

As more young Jews step out of the communal infrastructure, it may be up to roving rabbis like Nesselson to provide them with the spiritual guidance they still seek.

James Ponet
Slifka Center for Jewish Life | New Haven, Conn.
The unlikely architect of Jewish life at Yale

The refrain is familiar to countless Yale students: “Good evening and Shabbat shalom, ladies and gentlemen! Allow me to introduce myself: My name is Jim Ponet, class of 1968, and I am the oldest rabbi Yale has ever had.”

Ponet has been the campus’ Jewish chaplain since 1981 and is now retiring after an illustrious and celebrated career. He was instrumental in raising the millions of dollars necessary to construct the sprawling Slifka Center for Jewish Life at Yale, which transitioned the Jewish community out of a basement in New Haven and into the center of college life. And once the center was built, the charismatic Ponet helped draw the thousands of students that have made it a success.

Ponet didn’t intend to be a rabbi, let alone a campus visionary. When he arrived at Yale as an undergraduate in 1964, he was a French major who had legally changed his name from Podnetsky to sound less Jewish. When he left, he was a Religious Studies major and on his way to Hebrew Union College, where he was ordained in 1973. After nearly a decade in Israel, he returned to his alma mater, intending to stay for just a few years, but ending up as the unlikely high priest of New Haven. Looking back, he has described his Jewish journey as a fulfillment of the verse of Psalms: “even ma’asu ha-bonim hayta le-rosh pinah”—“the stone which the builders rejected has become the cornerstone.”

Jason Rubenstein
Mechon Hadar | New York, N.Y.
The soul of a post-denominational yeshiva

Mechon Hadar, an egalitarian community and yeshiva in New York, is the flagship of the independent minyan movement in America. And Rabbi Jason Rubenstein—“Rav Jason” to his students—is the heart of Mechon Hadar. In what can often be a hyper-intellectual environment, Rubenstein offers a personal and sensitive touch in his role as dean of students.

Rubenstein first joined the faculty of Hadar while completing his rabbinical studies at the Jewish Theological Seminary, where he was ordained in 2011. He has taught Talmud and Jewish thought to the yeshiva’s many students, while counseling and guiding them in their learning and spiritual development. While others are typically the institution’s public face in the op-ed pages and national Jewish press, Rubenstein is the soul of its Beit Midrash. “He makes himself deeply, personally available,” recalled Jana Jett Loeb, a former student. He is perpetually answering questions and distributing Jewish source texts to the many alumni with whom he remains in touch. “It’s not like he was afraid to say, ‘I don’t know where you should look,’ ” said Loeb. “It’s just that I never heard him say that.” He is as comfortable explaining the medieval rabbinic conception of the separation of synagogue and state as he is discussing the philosophy of Jürgen Habermas.

When not providing a warm and supportive presence at Hadar, Rubenstein can be found crisscrossing the country teaching and recruiting for the institution from Michigan to Colorado.

Elana Stein-Hain
Shalom Hartman Institute | New York, N.Y.
Modern Orthodoxy’s female forerunner

Elana Stein-Hain is not officially a rabbi, and she has been careful to avoid the label. But she is one of an elite group of Orthodox women who have been serving in para-rabbinic capacities across America over the last decade. As the community scholar at New York’s Lincoln Square Synagogue from 2008 to 2014, she taught advanced Torah classes, counseled congregants, presided over life-cycle events, and delivered sermons from the pulpit. In fact, when we put out a call for nominations for this list, she received more than any other candidate.

It’s not hard to see why. Stein-Hain is a graduate of Yeshiva University’s Program in Advanced Talmudic Studies. She received her doctorate in religion from Columbia University—where she studied under the famed Talmud scholar David Weiss HaLivni—and wrote her dissertation on the role of loopholes in Jewish law. She has lectured widely, covering an extensive array of subjects from Orthodox responses to biblical criticism to Jewish ethics of war. Finally, in addition to her synagogue duties at Lincoln Square and her guest lectures outside it, she taught at New York University’s Wagner School of Public Service.

A role model to many aspiring Orthodox female leaders, Stein-Hain co-founded the Orthodox Leadership Project in 2013 to help support other women pursuing similar paths. And this past April, she joined the Shalom Hartman Institute as its first director of Leadership Education, where she directs all of the organization’s lay and professional leadership development programs.

Jeremy Wieder
Yeshiva University | New York, N.Y.
A Rosh Yeshiva and academic Talmudist

Long before he became one of the rabbinic deans at Yeshiva University, Jeremy Wieder made national Jewish headlines when he became the one of the few Americans to win the International Bible Contest in Jerusalem in 1988, at the age of 17. He would go on to graduate summa cum laude from Y.U., where he also received a master’s in American Jewish history, before completing a Ph.D. in rabbinic literature at New York University. Today he is a professor of Talmud and Bible at Yeshiva University, where he serves as Rosh Yeshiva.

In a school that sometimes draws attention for the more conservative pronouncements of its religious leadership, Wieder often offers a moderating voice. He incorporates the scholarly tools of academic Talmud study into his daily shiurim for students, alongside more classical methods. He has spoken at length about how secular literature can inform and illuminate the understanding of traditional Jewish texts. And when the Orthodox community became embroiled in a debate over the theological acceptability of evolution and contemporary cosmology, Wieder delivered a public lecture explaining how scripture need not be read literally on these subjects.

Wieder has defended the role of the humanities in a religious education, saying, “It is very important for students to be exposed to other ways of thinking, even if they ultimately do not accept them. Such exposure induces a certain kind of intellectual humility and respect for others who have different ideas, while the lack of such exposure leads to a certain kind of unbridled arrogance and condescension.”

Over 1,000 of Wieder’s lectures on Talmud, Bible, and Jewish law can be found online, along with his meticulous recordings of the weekly Torah portions for aspiring readers.

David Wolkenfeld
Congregation Anshe Shalom B’nai Israel | Chicago, Ill.
A rising star of liberal Orthodoxy

Last summer, David Wolkenfeld assumed the pulpit of Anshe Shalom B’nai Israel in Chicago, a venerable Orthodox congregation established in 1892. His immediate predecessor, Rhodes Scholar Asher Lopatin, left big shoes to fill when he departed to take over Yeshivat Chovevei Torah rabbinical school, the bastion of left-wing Modern Orthodoxy. But if anyone is up to the challenge of succeeding Lopatin, it’s Wolkenfeld.

A Harvard History major who was ordained in 2008, Wolkenfeld quickly made his mark when he and his wife Sara became the Orthodox campus educators at Princeton’s Center for Jewish Life, as part of the Orthodox Union’s Jewish Learning Initiative on Campus. For five years, Wolkenfeld mentored and taught undergrads, grad students, and professors—Orthodox and not—offering instruction in Talmud, Bible, and Jewish law. He even organized an intercampus hands-on seminar on kosher slaughter. Wolkenfeld also designed an eruv for the area and generally breathed life into what had been one of the weakest Ivy League Orthodox communities. When he left, it was one of the most vibrant.

In recent years, Wolkenfeld has taken strong yet subtle stances on many issues at the heart of debates over Orthodoxy’s future. He has made the Jewish legal case for ordaining women as rabbis and advocated for the expansion of women’s roles in the Orthodox community, though he has questioned approaches like partnership minyanim. He has also pushed for a more inclusive Orthodox attitude toward LGBT Jews. With these and other conversations continuing to come to the fore in Modern Orthodoxy, expect voices like Wolkenfeld’s to as well.

Brian Zimmerman
Union for Reform Judaism | Dallas, Texas
The Reform movement’s shepherd of the South

In 2006, Brian Zimmerman left one synagogue to become the rabbi of dozens. After seven years as the spiritual leader of Beth Am, a large congregation in Tampa, Fla., he departed to assume the position of congregational network director for the South at the Union for Reform Judaism. This may sound like a staid administrative post. But it actually translates to “peripatetic agent of religious inspiration and creativity.”

Zimmerman, a 12th-generation rabbi ordained in 1993, is one of a handful of the Reform movement’s unsung heroes—rabbinic regional directors who work tirelessly to bolster the denomination’s synagogue life while not occupying an individual pulpit of their own.

A Film major in college, Zimmerman has spent the last eight years putting his personal ingenuity to work strengthening the nearly 200 Reform synagogues across the American South. He spends a portion of each month on the road, regularly serving as scholar-in-residence at these temples, where he can be found teaching, leading services, consulting on synagogue programming, distributing educational resources, and generally offering a sympathetic ear to congregations and their leaders. During any given week, he may be spotted in Georgia, North Carolina, Louisiana, Tennessee, Oklahoma, or back home in Dallas—just six of the 11 states in his jurisdiction. And in spare moments, he also helps oversee the region’s Reform summer camps.


You can help support Tablet’s unique brand of Jewish journalism. Click here to donate today.

Yair Rosenberg is a senior writer at Tablet. Subscribe to his newsletter, and follow him on Twitter and Facebook.

Yair Rosenberg is a senior writer at Tablet. Subscribe to his newsletter, listen to his music, and follow him on Twitter and Facebook.