Wengraf, Tom
Sage Publications, 2002
Buku Teks
Jakarta [t.p.] 1974
UI - Makalah dan Kertas Kerja
Thyer, Bruce A.
London : Sage Publications, 2001,
Buku Referensi
P.t the Centre for south-East Asia studies University of Hull 1989,
Buku Teks
New York American Academy of Pediatric 2002,
Buku Teks