The strongest advocate of this view is Henry Mintzberg, a professor at Canada's McGill University.

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At 16 he entered Canada's prestigious McGill University.

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The researchers, from McGill University in Canada and the University of Minnesota in the US, looked for studies that met pretty stiff quality criteria.

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However, perhaps the most imaginative advocate of the use of art in developing future business leaders is Nancy Adler, on the Desautels faculty of McGill University in Canada.

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Perhaps, however, the most effective coach of all is staring back at you from the bathroom mirror every morning, at least in the view of another business school, the Desautels Faculty at McGill University in Canada.

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Dr Scott Delaney, research director of emergency medicine at McGill University Health Center in Montreal, Canada, has also researched soccer-related head injury and agrees that head-to-head or elbow-to-head blows are the real risk.

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