Eadie, Edward N., autohr
[, Springer], 2012
eBooks
Dipboye, Robert L., author
Harcourt Brace College, 1994
Buku Teks
edited by A.A. Myers and P.S. Giller
Chapman & Hall, 1988
Buku Teks
Alcock, John, author
Sinauer Associates, 1989
Buku Teks
Rosenthal, Murray P., author
Hayden Book , 1975
Buku Teks