(1950). Concrete shell and barrel roofs (2nd ed.). [s.l.]: Cement and Concrete Association.
Παραπομπή Chicago StyleConcrete Shell and Barrel Roofs. 2nd ed. [s.l.]: Cement and Concrete Association, 1950.
Παραπομπή MLAConcrete Shell and Barrel Roofs. 2nd ed. [s.l.]: Cement and Concrete Association, 1950.
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