by Harvey Checkoway, Neil Pearce, Douglas J. Crawford-Brown
Oxford University Press, 1989
Buku Teks
Grobbee, Diederick E.
Jones and Bartlett Publishers , 2015
Buku Teks
Grobbee, Diederick E.
Jones & Bartlett Learning, 2015
Buku Teks
edited by Kyle Steenland
Oxford University Press, 1993
Buku Teks
MacMahon, Brian
Little, Brown and Company, 1970
Buku Teks