Newman, Barbara M.
Cengage Learning, 2018
Buku Teks SO
Newman, Barbara M.
Thomson and Wadsworth, 2006
Buku Teks SO
Newman, Barbara M.
Wadsworth and Cengage Learning, 2012
Buku Teks SO
Bartol, Curt R.
Pearson Education, Inc., 2008
Buku Teks
Beland, Irene L.
Macmillan, 1981
Buku Teks SO