Não informado. (1937). Concrete for railways. Portland Cement Association.
Cita Chicago Style (17a ed.)Não informado. Concrete for Railways. Chicago, Ill: Portland Cement Association, 1937.
Cita MLA (8a ed.)Não informado. Concrete for Railways. Portland Cement Association, 1937.
Precaución: Estas citas no son 100% exactas.