Anthony, Robert N. (Robert Newton), 1916-2006, author
Richard D. Irwin, 1974
Buku Teks
Welsch, Glenn A., author
Learning System Company, 1977
Buku Teks
Edwards, James Don, author
Richard D. Irwin, 1975
Buku Teks
Weston, J. Fred (John Fred), 1916-, author
Richard D. Irwin , 1982
Buku Teks
Terry, George Robert, author
Richard D. Irwin, 1982
Buku Teks