Não informado. (2003). Concrete builder. Portland Cement Association.
Chicagoスタイル(17版)引用形式Não informado. Concrete Builder. Chicago, Ill: Portland Cement Association, 2003.
MLA(8版)引用形式Não informado. Concrete Builder. Portland Cement Association, 2003.
警告: この引用は必ずしも正確ではありません.