Private Development Corporation of the Philippines. (1973). The concrete aggregates industry. s.n.].
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रPrivate Development Corporation of the Philippines. The Concrete Aggregates Industry. [Makati, Rizal: s.n.], 1973.
एमएलए (9वां संस्करण) प्रशस्ति पत्रPrivate Development Corporation of the Philippines. The Concrete Aggregates Industry. s.n.], 1973.
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