Buttrick, R. (2000). Project workout: A tool kit for reaping the rewards from all your business (2nd ed.). Pearson Education Ltd.
Chicago-tyylinen lähdeviittausButtrick, Robert. Project Workout: A Tool Kit for Reaping the Rewards from All Your Business. 2nd ed. London: Pearson Education Ltd, 2000.
MLA-viiteButtrick, Robert. Project Workout: A Tool Kit for Reaping the Rewards from All Your Business. 2nd ed. Pearson Education Ltd, 2000.
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