Nichols, Eugene D.
Rinehart Press, 1975
Buku Teks
Nichols, Eugene D.
Holt, Rinehart and Winston, 1971
Buku Teks
Horner, Donald H., author
Rinehart, 1973
Buku Teks
White, Paul A., author
Dickenson, 1970
Buku Teks
Tan, S.T. , author
PWS Publishing Company, 1994
Buku Teks