O`Shea, Robert P. (Robert Paul), 1953-, author
Harcourt Brace Jovanovich, 1993
Buku Teks
Weisman, Herman M.
Charles E. Merrill Publishing Company, 1980
Buku Teks
herausgegeben von Hartmut Günther, Otto Ludwig
Walter de Gruyter, 1994
Buku Referensi
Ferre, John P., author
Charles E. Merrill Pub. Co., 1983
Buku Referensi
Churchill Livingstone, 2003
Buku Teks