5James Douglas,“ Political Theories of Nonprofit Organization”, in Walter W. Powell ed. ,The Nonprofit Sector, Yale University Press, 1987: 43.
6Merle Curti,“ Tradition and Innovation in American Philanthropy”, Proceedings of the American Philosophical Society, Vol.105, No. 2, April, 1961:146 -156.
7Irvin G. Wyllie,“The Search for an American Law of Charity, 1776 - 1884”, The Mississippi Valley Historical Review,Vol. 46, No. 2 (Sept. , 1959), pp. 203 -221.
8Merle Curti. ,“Tradition and Innovation in American Philanthropy”, Proceedings of the American Philosophical Society, Vol.105, No. 2, April, 1961: 146-156.
9See John G. Simon. “The Tax Treatment of Nonprofit Organizations: A Review of Federal and State Policies”. in Walter W.Powell ed. The Nonprofit Sector. Yale University Press, 1987: 69.
10Gabriel Rudney, “The Scope and Dimensions of Nonprofit Activity”, in Waiter W. Powell ed. The Nonprofit Sector. Yale University Press, 1987 : 55.
