Cather, Willa, 1873-1947
Vintage Books, 1992
Buku Teks SO
Cather, Willa, 1873-1947
A Signet Classic, 1988
Buku Teks
edited by Gregory A. Kimble, Michael Wertheimer, Charlotte White
American Psychological Association, 1991
Buku Teks SO
Beek, Leo
Van Gorcum, 1985
Buku Referensi
Kohler, Littleton
State University , 1951
Buku Teks SO