Villablanca, R. E. (1976). Suggested test items for elementary school science IV developed by the University of the Philippines Science Education Center.
توثيق أسلوب شيكاغو (الطبعة السابعة عشر)Villablanca, Rolando Enerez. Suggested Test Items for Elementary School Science IV Developed by the University of the Philippines Science Education Center. 1976.
توثيق جمعية اللغة المعاصرة MLA (الإصدار التاسع)Villablanca, Rolando Enerez. Suggested Test Items for Elementary School Science IV Developed by the University of the Philippines Science Education Center. 1976.
تحذير: قد لا تكون هذه الاستشهادات دائما دقيقة بنسبة 100%.