Private Development Corporation of the Philippines. (1973). The portland cement industry. s.n.].
芝加哥风格引文Private Development Corporation of the Philippines. The Portland Cement Industry. [Makati, Rizal: s.n.], 1973.
MLA引文Private Development Corporation of the Philippines. The Portland Cement Industry. s.n.], 1973.
警告：这些引文格式不一定是100％准确.