Nichols, Eugene D., author
Holt, Rinehart and Winston, 1971
Buku Teks SO
Bitter, Gary G., author
Allyn and Bacon, 1989
Buku Teks SO
Garstens, Helen L., author
Macmillan, 1969
Buku Teks SO
Phares Odaffer, Randall Charles, Thomas Cooney, John Dossey, Jane Schielack
Pearson Addison Wesley, 2008
Buku Teks SO
Devine, Donald F., author
John Wiley & Sons, 1977
Buku Teks SO