2Youngs P. Principal leadership for professional development to build school capacity. Educational Administration Quarterly. 2002,38(5): 643 - 670.
3Marks H M & Printy S M. Principal leadership and school performance: An integration of transformational and instructional leadership. Educational Administration Quarterly 2003,39(3): 370 - 390.
4Cranston N C. School - based management, leaders and leadership: Change and challenges for principals. International Studies in Educational Administration. 2002,30( 1 ) : 2 - 12.