Dyfyniad APA

Callaghan, J. (1992). Costing for contracts. Directory of cocial change.

Dyfyniad Arddull Chicago

Callaghan, John. Costing for Contracts. London: Directory of cocial change, 1992.

Dyfyniad MLA

Callaghan, John. Costing for Contracts. Directory of cocial change, 1992.

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