APA-viite

PN Kalla. (2006). Communication skills for extension workers. Agrotech publishing academy.

Chicago-tyylinen lähdeviittaus

PN Kalla. Communication Skills for Extension Workers. Udaipur: Agrotech publishing academy, 2006.

MLA-viite

PN Kalla. Communication Skills for Extension Workers. Agrotech publishing academy, 2006.