Larsen, S. T. (1973). Report of studies on the organization, O and M and equipment of the National Irrigation Administration of the Government of the Philippines [microform]. Photoduplication Service University of the Philippines Library.
توثيق أسلوب شيكاغو (الطبعة السابعة عشر)Larsen, S. T. Report of Studies on the Organization, O and M and Equipment of the National Irrigation Administration of the Government of the Philippines [microform]. Quezon City: Photoduplication Service University of the Philippines Library, 1973.
توثيق جمعية اللغة المعاصرة MLA (الإصدار التاسع)Larsen, S. T. Report of Studies on the Organization, O and M and Equipment of the National Irrigation Administration of the Government of the Philippines [microform]. Photoduplication Service University of the Philippines Library, 1973.