眼睛瞎了？也不知道上牛津大学图书馆查一下真假？
下面是张维迎牛津大学博士论文库的链接
http://solo.ouls.ox.ac.uk/primo_library/libweb/action/search.do?vid=OXVU1&fromLogin=true
输入“weiying zhang”
得到以下结果。如果你不懂英文，让别人查也可以。

Entrepreneurial ability, personal wealth and the assignment of principalship : an entrepreneurial/contractual theory of the firm (View details)
Weiying Zhang 1959- University of Oxford. Faculty of Social Studies.; Nuffield College.
Thesis (D.Phil.)--University of Oxford, 1994. 1994 ii, 197 leaves ; 31 cm.
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