Morris، Elizabeth A. (1986). "Charles Wesley Ferguson ,1922–1986"(PDF). Tree-Ring Bulletin. Laboratory of Tree-Ring Research, University of Arizona. ج. 46: 1. مؤرشف من الأصل(PDF) في 2012-04-13.
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Morris، Elizabeth A. (1986). "Charles Wesley Ferguson ,1922–1986"(PDF). Tree-Ring Bulletin. Laboratory of Tree-Ring Research, University of Arizona. ج. 46: 1. مؤرشف من الأصل(PDF) في 2012-04-13.
