Suchar, Charles S.
Holt, Rinehart and Winston, 1978
Buku Teks
Inderbitzin, Michelle Lee, author
SAGE, 2015
Buku Teks
J.B.Lippincott, 1975
Buku Teks
Little, Craig B.
F.E. Peacock Publishers, 1989
Buku Teks
Hills, Struart L.
McGraw-Hill , 1980
Buku Teks