 Beginning around 1964, the more than a decade of challenges to U.S. censorship laws applied to literary novels such as "Lady Chatterley's Lover", "Portnoy's Complaint", and "Naked Lunch" had redefined legal standards for obscenity.Susan Stryker cites Tom Norman's bibliography of American gay erotic paperbacks to note that thirty gay paperback books were published in 1965, and that over a hundred were in 1966.Many of these publishers had their roots in publishing beefcake, or "male physique" magazines in the 1950s, precursors to explicit gay pornographic magazines.