Swaim, 200 4 . The principle is to ...... D A V I S, Stephen and H A LT I W A N GER, John., 199 6 , J ob C reation and de s truction,. Cambridge, M I T Press.
Author manuscript, published in "N/P"
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halshs-00186363, version 1 - 8 Nov 2007
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halshs-00186363, version 1 - 8 Nov 2007
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