Philippines. Regional Development Council, Region I. (2004). Regional physical framework plan: 2004-2030: Ilocos region. NEDA,/RDC I.
Chicago-viite (17. p.)Philippines. Regional Development Council, Region I. Regional Physical Framework Plan: 2004-2030: Ilocos Region. [San Fernando City, La Union: NEDA,/RDC I, 2004.
MLA-viite (9. p.)Philippines. Regional Development Council, Region I. Regional Physical Framework Plan: 2004-2030: Ilocos Region. NEDA,/RDC I, 2004.
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