Taft, Donald R., author
Macmillan, 1964
Buku Teks
Taft, Donald R., author
Macmillan, 1964
Buku Teks
Lanier, Mark M., author
Westview Press, a member of the Perseus Books Group, 2015
Buku Teks
Carrabine, Eamonn, author
Routledge, 2009
Buku Referensi
Copes, Heith, author
McGraw-Hill, 2009
Buku Teks