edited by Ray Laurence, Joanne Berry
Routledge, 1998
Buku Teks
London Routledge , 2000
Buku Teks
Charlesworth, M. P., author
Oxford University Press, 1951
Buku Teks
Sickle, C.E. van, author
Houghton Mifflin, 1947
Buku Teks
Grant, Michael
Routledge, 1999
Buku Teks