Philippines. Department of Public Works, Transportation and Communications, & Planning and Project Development Office. (1972). Pre-feasibility study: Marikina-Infanta road. PPDO.
Chicago-viite (17. p.)Philippines. Department of Public Works, Transportation and Communications, ja Planning and Project Development Office. Pre-feasibility Study: Marikina-Infanta Road. Manila: PPDO, 1972.
MLA-viite (9. p.)Philippines. Department of Public Works, Transportation and Communications, ja Planning and Project Development Office. Pre-feasibility Study: Marikina-Infanta Road. PPDO, 1972.
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