National Library. Bibliography Division & Del Rosario, I. A. (1978). Directory of publishers and printers. Bibliography Division, National Library of the Philippines.
Chicago-viite (17. p.)National Library. Bibliography Division ja Iluminada A. Del Rosario. Directory of Publishers and Printers. Manila: Bibliography Division, National Library of the Philippines, 1978.
MLA-viite (9. p.)National Library. Bibliography Division ja Iluminada A. Del Rosario. Directory of Publishers and Printers. Bibliography Division, National Library of the Philippines, 1978.
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