Birkets, Sven P
Allyn and Bacon, 1993
Buku Teks
edited by Ralph Cohen
Sheridan Press, 1989
Buku Referensi
Ryan, Michael, 1951-, author
Wiley-Blackwell, 2017
Buku Teks SO
edited by Julie Rivkin and Michael Ryan
John Wiley & Sons, 2017
Buku Teks SO
Duke University Press, 1995
Buku Teks