Foster, Jeannette H. (Jeannette Howard)
Sex Variant Women in Literature: A Historical and Quantitative Survey is a 1956 study written by Jeannette Howard Foster chronicling approximately 2,600 years of female same-sex attraction in literature, beginning with Sappho's works in 6th century BC and ending with Patricia Highsmith's The Price of Salt in 1952. (This summary is from Wikipedia.)
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