Oliva, V. G. (1974). The influence of the Camarines norte National Agricultural School (CNNAS) on the agricultural practices, particularly rice culture, in three rice-growing barrios of Camarines norte [microform]. Photoduplication Service University of the Philippines Library.
توثيق أسلوب شيكاغو (الطبعة السابعة عشر)Oliva, Virgilio G. The Influence of the Camarines Norte National Agricultural School (CNNAS) on the Agricultural Practices, Particularly Rice Culture, in Three Rice-growing Barrios of Camarines Norte [microform]. Quezon City: Photoduplication Service University of the Philippines Library, 1974.
توثيق جمعية اللغة المعاصرة MLA (الإصدار التاسع)Oliva, Virgilio G. The Influence of the Camarines Norte National Agricultural School (CNNAS) on the Agricultural Practices, Particularly Rice Culture, in Three Rice-growing Barrios of Camarines Norte [microform]. Photoduplication Service University of the Philippines Library, 1974.