Gaya APA

Field, B, C., Field, M, K. (2013). Environmental economics: an introduction, Sixth Edition (Ed.ke-6). Yogyakarta: Salemba Empat.

Gaya MLA

Field, Barry, C.., Field, Martha, K.. "Environmental economics: an introduction, Sixth Edition". Ed.ke-6 Yogyakarta: Salemba Empat, 2013. Text.