White, Morton G.
[Publisher not identified], 1955
Buku Teks SO
New York Mentor book 1954,
Buku Teks
edited by Stuart Brown, Diane Collinson, Robert Wilkinson
Roudledge, 1996
Buku Referensi
edited by Stuart C. Brown, Diane Collinson, Robert Wilkinson
Routledge, 1998
Buku Teks SO
Hampshire, Stuart
New American Library, 1960
Buku Teks SO