Ministry of Tourism Republic of Indonesia, 2016
Multimedia
Jessup, Ronald
Macdonald, 1968
Buku Teks SO
Priestley, John Boynton, 1894-1984
Garden City Books, 1959
Buku Teks SO
Christian Baumgartner , Martin Uitz, Karl Krainer, Peter Hasslacher
The Federal Press Service, 2002
Buku Referensi
Moore, Raylyn
Bowling Green : Bowling Green University Popular, 1974
Buku Teks SO