Schumaker, Paul, author
Blackwell Publishing, 2008
Buku Teks SO
by Robert Eccleshall ... [et al]
Routledge, 1994
Buku Teks
Sivaramakrishnan, Arvind, author
Texts, 2017
Buku Teks
Corbett, Sister Thomas Albert
University of America Press, 1950
Buku Teks
Tannenbaum, Donald G., author
Wadsworth/Thomson learning, 2004
Buku Teks SO