Gray, W. S. (1947). Reinforced concrete water towers, bunkers, silos, and gantries (2d ed.). London: Concrete publications limited.
Παραπομπή Chicago StyleGray, William Samuel. Reinforced Concrete Water Towers, Bunkers, Silos, and Gantries. 2d ed. London: Concrete publications limited, 1947.
Παραπομπή MLAGray, William Samuel. Reinforced Concrete Water Towers, Bunkers, Silos, and Gantries. 2d ed. London: Concrete publications limited, 1947.
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