Berger, Morroe, author
D. Van Nostrand, 1954
Buku Teks
Udy, Stanley H., 1928-, author
Prentice-Hall, 1970
Buku Teks
Carroll, Charles R., author
McGraw-Hill, 2000
Buku Teks
Tomasson, Richard F., author
Random Home, 1970
Buku Teks
Tinker, Anthea, author
Longman , 1984
Buku Teks