Fibri Rommy, author
Pusat Data dan Analisa Tempo, 2008
Buku Teks
Vaux, Kenneth L
Westerview Press, 1992
Buku Teks
Leonhardt, Rudolf Walter
Munchen : R. Piper & Co Verlag, 1967
Buku Teks
[publisher not identified], [date of publication not identified]
Naskah
Tuah Arieyanda Setiawan, author
Universitas Indonesia, 2009
UI - Skripsi (Open)