A 1977 paper titled "Asexual and Autoerotic Women: Two Invisible Groups", by Myra T. Johnson, is explicitly devoted to asexuality in humans. Johnson defines asexuals as those men and women "who, regardless of physical or emotional condition, actual sexual history, and marital status or ideological orientation, seem to "prefer" not to engage in sexual activity." She contrasts autoerotic women with asexual women: "The asexual woman ... has no sexual desires at all the autoerotic woman ... recognizes such desires but prefers to satisfy them alone." Johnson's evidence is mostly letters to the editor found in women's magazines written by asexual/autoerotic women. She portrays them as invisible, "oppressed by a consensus that they are non-existent," and left behind by both the sexual revolution and the feminist movement. Johnson argued that society either ignores or denies their existence or insists they must be ascetic for religious reasons, neurotic, or asexual for political reasons.