U. S. Bureau of Insular Affairs & iGLibrary (online resource). (1911). Summary of Commerce of the Philippine Islands. Photoduplication Service. University of the Philippines Library.
Chicago-referens (17:e uppl.)U. S. Bureau of Insular Affairs och iGLibrary (online resource). Summary of Commerce of the Philippine Islands. Quezon City: Photoduplication Service. University of the Philippines Library, 1911.
MLA-referens (9:e uppl.)U. S. Bureau of Insular Affairs och iGLibrary (online resource). Summary of Commerce of the Philippine Islands. Photoduplication Service. University of the Philippines Library, 1911.
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