Callison, W. L., & McAllister, C. H. (1999). Elementary school principal's handbook. Technomic.
Dyfyniad Arddull ChicagoCallison, William L., and Carol H. McAllister. Elementary School Principal's Handbook. Lancaster, PA: Technomic, 1999.
Dyfyniad MLACallison, William L., and Carol H. McAllister. Elementary School Principal's Handbook. Technomic, 1999.
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