Cita APA (7a ed.)

Kumar, S., & Kumar, S. (2012). Biogas. IntechOpen.

Cita Chicago Style (17a ed.)

Kumar, Sunil, y Sunil Kumar. Biogas. [Place of publication not identified]: IntechOpen, 2012.

Cita MLA (9a ed.)

Kumar, Sunil, y Sunil Kumar. Biogas. IntechOpen, 2012.