Callaghan, J. (1992). Costing for contracts. Directory of cocial change.
芝加哥风格引文Callaghan, John. Costing for Contracts. London: Directory of cocial change, 1992.
MLA引文Callaghan, John. Costing for Contracts. Directory of cocial change, 1992.
警告：这些引文格式不一定是100％准确.