Schwarz, Ted
Ohio Writer's Digest Books, 1990
Buku Teks SO
by Cal M. Lague [and others]
Allyn and Bacon, 1982
Buku Teks SO
Manneke Budiman
Fakultas Ilmu Pengetahuan Budaya Universitas Indonesia, 1989
UI - Skripsi Membership
Benton, Ted
Routledge & Kegan Paul , 1977
Buku Teks SO
Chih, Ted Yang
McGraw-Hill, 1996
Buku Teks SO