edited by Phil Hubbard and Rob Kitchin
Sage, 2011
Buku Teks
De Blij, Harm J., author
John Wiley & Sons, 1995
Buku Teks
Malinowski, Jon C., author
McGraw-Hill, 2012
Buku Teks
by Jerome D. Fellmann, Mark D. Bjelland, Arthur Getis, Judith Getis
McGraw-Hill, 2010
Buku Teks
Valentine, Gill, author
Prentice-Hall, 2001
Buku Teks