Ellison, B. K. (1973). Labour intensive methods in road construction. Dept. of Public Works, Roads and Bridges Division.
Chicago Style aipamenaEllison, B. K. Labour Intensive Methods in Road Construction. [Port Moresby]: Dept. of Public Works, Roads and Bridges Division, 1973.
MLA aipamenaEllison, B. K. Labour Intensive Methods in Road Construction. Dept. of Public Works, Roads and Bridges Division, 1973.
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