Shulamith Firestone, a leading thinker of second-wave feminism and co-founder of the New York Radical Women group, was declared dead August 28 at age 67, the New York City Office of Chief Medical Examiner has confirmed. (Word had trickled into the comments section of her JWA biography.)

Firestone, a radical feminist and activist, was the author of the groundbreaking 1970 book, The Dialectic of Sex: The Case for Feminist Revolution. She left politics in the early 1970s and later fell into obscurity.

UPDATE: The Villager has more information, some of it disturbing, about Firestone’s death. They report she was likely dead for about a week before her body was discovered in her apartment Tuesday by her landlord.