Amstrong, Michael
Crest Publishing House, 1999
Buku Referensi
edited by Keith J. Holyoak, Robert G. Morrison
Cambridge University Press, 2005
Buku Referensi
Bakich, Michael E.
Cambridge University Press, 1999
Buku Referensi
Mackerras, Colin
Cambridge University Press, 1991
Buku Referensi
edited by Anita L. Vangelisti, Daniel Perlman
Cambridge University Press, 2006
Buku Referensi