Philippines (Republic) Industrial Development Center. (1962). Provincial economic surveys: Province of Abra. IDC.
Citazione stile Chigago Style (17a edizione)Philippines (Republic) Industrial Development Center. Provincial Economic Surveys: Province of Abra. Manila: IDC, 1962.
Citatione MLA (9a ed.)Philippines (Republic) Industrial Development Center. Provincial Economic Surveys: Province of Abra. IDC, 1962.
Attenzione: Queste citazioni potrebbero non essere precise al 100%.