Baldwin, Thomas Whitfield, 1890-, author
The University of Illinois Press, 1943
Buku Teks
Dowden, Edward, author
American Book, [date of publication not identified]
Buku Teks
Prentice-Hall, 1993
Buku Teks
Murphy, Antoin E., author
Rajawali, 2011
Buku Teks
Petty, Geoffrey
Elex Media Komputindo, 1997
Buku Teks