Philippines. Department of Public Works, Transportation and Communications, & Planning and Project Development Office. (1972). Pre-feasibility study: Marikina-Infanta road. PPDO.
Chicago-referens (17:e uppl.)Philippines. Department of Public Works, Transportation and Communications, och Planning and Project Development Office. Pre-feasibility Study: Marikina-Infanta Road. Manila: PPDO, 1972.
MLA-referens (9:e uppl.)Philippines. Department of Public Works, Transportation and Communications, och Planning and Project Development Office. Pre-feasibility Study: Marikina-Infanta Road. PPDO, 1972.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.