This subseries comprises photocopied book excerpts, journal and magazine articles that reflect significant aspects of Harry Hay's research interests. Hay identified readings in (a) the political dimensions of folk music and culture, and (b) evidence for the presence of homosexual minorities across a range of historical periods and societies, as key elements in his conceptualization of the Mattachine Society in the late 1940s. These texts appear in two folders labeled "Mattachine Research." A third folder contains two articles on archetypal psychology in Jungian thought (1976), and one on formulating a new age, "new human agenda" (1978). These articles pertain to Hay's contributions to the Radical Faerie movement in the late 1970s and beyond. A miscellaneous folder at the end of the subseries is comprised of mostly undated material including developed notes, a portion of an untitled historical essay, and a historical note on gay New York. Highlighting and margin notes by Hay appear on some the material.