New horizons world guide
edited by Gerald W. Whitted
Pan American World Airways, 1971
 Buku Referensi
New horizons world guide
edited by Gerald W. Whitted
Pan American World Airways, 1963
 Buku Referensi
World travel encyclopedian : insight guides
APA Publications , 2007
 Buku Referensi
New horizons world guide : Pan American's Travel Facts about 108 countries
edited by Gerald W. Whitted
Pan American Airways, 1963
 Buku Teks SO
New horizons world guide : Pan Am's Travel Facts about 138 countries
edited by Gerald W. Whitted
Pan American World Airways, 1971
 Buku Teks SO