Cather, Willa, 1873-1947
A Signet Classic, 1988
Buku Teks
Sucahyani Dwi Astuti
Program Pascasarjana Universitas Indonesia, 2013
UI - Tesis Membership
edited by Gregory A. Kimble, Michael Wertheimer, Charlotte White
American Psychological Association, 1991
Buku Teks
Kohler, Littleton
State University , 1951
Buku Teks
Cramer, John
Allen & Unwin, 1989
Buku Teks