Buttrick, R. (1997). The project workout: A tool kit for reaping the rewards from all your business projects. Pitman.
Chicago-viite (17. p.)Buttrick, Robert. The Project Workout: A Tool Kit for Reaping the Rewards from All Your Business Projects. London: Pitman, 1997.
MLA-viite (9. p.)Buttrick, Robert. The Project Workout: A Tool Kit for Reaping the Rewards from All Your Business Projects. Pitman, 1997.
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