French, Wendell
Houghton Mifflin, 1974
Buku Teks
Sikula, Andrew F., author
Wiley, 1976
Buku Teks
Kindall, Alva F., author
Richard D. Irwin, 1964
Buku Teks
Greenlaw, Paul S., author
Harper & Row, 1986
Buku Teks
Strauss, George, author
Prentice-Hall, 1980
Buku Teks