Hontiveros, G. (2004). Butuan of a thousand years. Butuan City Historical and Cultural Foundation.
Citazione stile Chigago Style (17a edizione)Hontiveros, Greg. Butuan of a Thousand Years. Butuan City: Butuan City Historical and Cultural Foundation, 2004.
Citatione MLA (9a ed.)Hontiveros, Greg. Butuan of a Thousand Years. Butuan City Historical and Cultural Foundation, 2004.
Attenzione: Queste citazioni potrebbero non essere precise al 100%.