Philippines. National Economic Development Authority. (1975). Development in Region I: An annotated bibliography. National Economic Development Authority.
توثيق أسلوب شيكاغو (الطبعة السابعة عشر)Philippines. National Economic Development Authority. Development in Region I: An Annotated Bibliography. [San Fernando, La Union]: National Economic Development Authority, 1975.
توثيق جمعية اللغة المعاصرة MLA (الإصدار التاسع)Philippines. National Economic Development Authority. Development in Region I: An Annotated Bibliography. National Economic Development Authority, 1975.
تحذير: قد لا تكون هذه الاستشهادات دائما دقيقة بنسبة 100%.