Forbes, W. C. (1977). The Philippine islands [microform]. Photoduplication Service, University of the Philippines Library.
Chicago-referens (17:e uppl.)Forbes, William Cameron. The Philippine Islands [microform]. Quezon City: Photoduplication Service, University of the Philippines Library, 1977.
MLA-referens (9:e uppl.)Forbes, William Cameron. The Philippine Islands [microform]. Photoduplication Service, University of the Philippines Library, 1977.
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