Gaya APA

Zhou, P., Poh, K, L. (2007). A survey of data envelopment analysis in energy and environmental study (ResearchGate). Singapore: ResearchGate.

Gaya MLA

Zhou, P.., Poh, Kim, Leng. "A survey of data envelopment analysis in energy and environmental study". ResearchGate Singapore: ResearchGate, 2007. Article.