1[1,17]Ⅱ.C.Tenure System at the University of Pennsylvania[Z]http://www.upenn.edu/assoc-provost/handbook/ii_c_1.html.
2[3,10]1940 Statement of Principles on Academic Freedom and Tenure with 1970 Interpretive Comments[Z].http://www.aaup.org/statements/Redbook / 1940stat.htm.
