Richards, Jill, authour
George Allen and Unwin, 1979
Buku Teks
edited by James Flood, Julie M. Jensen, Diane Lapp, James R. Squire
Macmillan, 1991
Buku Referensi
Centre for language in primary education, 1990
Buku Teks
Sriyeti
Fakultas Ilmu Pengetahuan dan Budaya Universitas Indonesia, 2005
UI - Tesis Membership
Cox, Brian
Athenaeum Press, 1999
Buku Teks SO