APA stil citiranja

Zuman, P., & Rupp, E. B. (2006). Humic acids: Humic acids : are they natural products? Croatica chemica acta, p. 9.

Chicago stil citiranja

Zuman, Petr, and Elinore B. Rupp. "Humic acids: Humic acids : are they natural products?" 2006: 9.

MLA stil citiranja

Zuman, Petr, and Elinore B. Rupp. "Humic acids: Humic acids : are they natural products?" 2006: 9.