HEITKAMP, J. H. Process plant construction estimating standars: Siteworkk, piling, concrete. Volume I. Richardson Engineering Sevice.
Chicago-viite (17. p.)HEITKAMP, John H. Process Plant Construction Estimating Standars: Siteworkk, Piling, Concrete. Volume I. Richardson Engineering Sevice.
MLA-viite (8. p.)HEITKAMP, John H. Process Plant Construction Estimating Standars: Siteworkk, Piling, Concrete. Volume I. Richardson Engineering Sevice.
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