Villamor, I., & Lopez, F. (1975). La antiqua escritura filipina deducida por I. Villamor del Belarmino y otros antiquos documentos. The ancient Filipino writing drawn from Belarmino and other ancient documents [microform]. Photoduplication Service, University of the Philippines Library.

Villamor, Ignacio, and Francisco Lopez. La Antiqua Escritura Filipina Deducida Por I. Villamor Del Belarmino Y Otros Antiquos Documentos. The Ancient Filipino Writing Drawn from Belarmino and Other Ancient Documents [microform]. Quezon City: Photoduplication Service, University of the Philippines Library, 1975.

Villamor, Ignacio, and Francisco Lopez. La Antiqua Escritura Filipina Deducida Por I. Villamor Del Belarmino Y Otros Antiquos Documentos. The Ancient Filipino Writing Drawn from Belarmino and Other Ancient Documents [microform]. Photoduplication Service, University of the Philippines Library, 1975.