Dumangas, M. L., & Vallejo, R. M. (1974). List of patentees to whom patents were issued by the Philippines Patents Office during the period 1948-1961 with a subject index to patents.
Chicago Style (17th ed.) CitationDumangas, Marianita L., and Rosa M. Vallejo. List of Patentees to Whom Patents Were Issued by the Philippines Patents Office During the Period 1948-1961 with a Subject Index to Patents. Quezon City : Institute of Library Science, University of the Philippines Diliman, 1974.
MLA (9th ed.) CitationDumangas, Marianita L., and Rosa M. Vallejo. List of Patentees to Whom Patents Were Issued by the Philippines Patents Office During the Period 1948-1961 with a Subject Index to Patents. 1974.
Warning: These citations may not always be 100% accurate.