De Blij, Harm J., author
John Wiley & Sons, 2005
Buku Teks
Getis, Arthur, author
Macmillan, 1985
Buku Teks
Hartshorn, Truman Asa, author
John Wiley & Sons, 1980
Buku Teks
Trewartha, Glenn T., author
McGraw-Hill, 1967
Buku Teks
Trewartha, Glenn T., author
McGraw-Hill, 1967
Buku Teks