Brewer, Richard, author
Saunders College Publishing, 1982
Buku Teks
Universitas Indonesia
UI Press, 2004
Buku Referensi
Jakarta : Perpustakaan Nasional RI
Majalah, Jurnal, Buletin
Kaufmann, Christian
Basel Pharos 1972
Buku Teks
Jakarta : Pustaka Rakyat
Majalah, Jurnal, Buletin