Krooss, Herman Edward, 1912-1975, author
Prentice-Hall, 1972
Buku Teks
Cochran, Thomas C.
McGraw-Hill, 1972
Buku Teks
Patrick, John
Macmillan Publishing Company, 1984
Buku Teks
Quint, Howard H
Dorsey Press, 1968
Buku Teks
Adams, James Truslow, author
1946
Buku Referensi