Omoto, Keiichi and Ueda, Shintaro and Goriki, Kazuaki and Takahashi, Norio and Misawa, Shogo and Pagaran, Ildefonso G (1981) Population genetic studies of the Philippine Negritos. III. Identification of the carbonic anhydrase-1 variant with CA1 Guam. American journal of human genetics, 33 (1). p. 105.
Schreurs, Peter (1981) THE ANGRY DAYS OF SURIGAO, 1898-1899:(OR: THE DRAMA BEHIND F. GONZALEZ STREET, CEBU CITY). Philippine Quarterly of Culture and Society, 9 (1). pp. 17-32.