Philippines (Republic) National Irrigation Administration & United States Bureau of Reclamation. (1971). Land classification and supporting studies on the Upper Pampanga River Project. s.n.].
Chicago-viite (17. p.)Philippines (Republic) National Irrigation Administration ja United States Bureau of Reclamation. Land Classification and Supporting Studies on the Upper Pampanga River Project. [Quezon City: s.n.], 1971.
MLA-viite (9. p.)Philippines (Republic) National Irrigation Administration ja United States Bureau of Reclamation. Land Classification and Supporting Studies on the Upper Pampanga River Project. s.n.], 1971.
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