De Guzman, A. Fertility differences in Region II: The effects of age structure and marital composition on municipal birth rates in 1973. Development and maintenance of a sample vital registration system in the Philippines : seminar proceedings, May 15-16, 1975..
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रDe Guzman, Alejandro. "Fertility Differences in Region II: The Effects of Age Structure and Marital Composition on Municipal Birth Rates in 1973." Development and Maintenance of a Sample Vital Registration System in the Philippines : Seminar Proceedings, May 15-16, 1975. .
एमएलए (9वां संस्करण) प्रशस्ति पत्रDe Guzman, Alejandro. "Fertility Differences in Region II: The Effects of Age Structure and Marital Composition on Municipal Birth Rates in 1973." Development and Maintenance of a Sample Vital Registration System in the Philippines : Seminar Proceedings, May 15-16, 1975., .