Margaret Kalacska, G. Arturo Sanchez-Azofeifa, editor
CRC Press, Taylor & Francis Group, 2008
Buku Teks
Kalacska, Margaret
CRC Press, 2008
Multimedia
edited by Jose I. Furtado
Harwood Academic , 1990.
Buku Teks
Joaquin, Nick
University of Queensland Press, 1972
Koleksi Publik
Manson-Bahr, P.E.C.
Bailliere Tindall , 1982
Buku Teks