Gaya APA

Hikmawati, I., Sriwanto, S. (2001). Geografi Regional Negara Maju . Purwokerto: FKIP UMP.

Gaya MLA

Hikmawati, Isna., Sriwanto, Sigid. "Geografi Regional Negara Maju". Purwokerto: FKIP UMP, 2001. Text.