De Guzman, R. P. (1970). A review of the regional delineation in the Philippines. Cooperative Regional Development Project, National Development Research Center.
Παραπομπή σε μορφή Chicago (17η εκδ.)De Guzman, Raul Policarpio. A Review of the Regional Delineation in the Philippines. Quezon City: Cooperative Regional Development Project, National Development Research Center, 1970.
Παραπομπή σε μορφή MLA (9th εκδ.)De Guzman, Raul Policarpio. A Review of the Regional Delineation in the Philippines. Cooperative Regional Development Project, National Development Research Center, 1970.
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