Gaya APA

dll., P, E, S, D. (2006). Seri Ensiklopedia IPS Mapping the World 2 : Observation and Measurement . : Pakar Raya.

Gaya MLA

dll., Peter, Eva,, Stella, Douglas,. "Seri Ensiklopedia IPS Mapping the World 2 : Observation and Measurement". : Pakar Raya, 2006. Text.