Quark/ was an American anthology book series devoted to avant-garde science fiction and related material, edited by writer and critic Samuel R. Delany and poet and editor Marilyn Hacker; four volumes were published in 1970 and 1971. The editors, once married, were among the foremost homosexual activist/writers in the following decades. The volumes in the series are: * Quark/1 * Quark/2 * Quark/3 * Quark/4