Pigors, Paul, author
McGraw-Hill , 1961
Buku Teks
Pigors, Paul, author
McGraw-Hill , 1969
Buku Teks
Pigors, Paul, author
McGraw-Hill, 1981
Buku Teks
Scott, Walter Dill, author
McGraw-Hill, 1959
Buku Teks
Cayer, N. Joseph, author
Thomson wadsworth, 2004
Buku Teks