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			 F:  | 
			
			 1. Edmund A. Bowles, “The Symbolism of the Organ in the Middle Ages: A Study in the History of Ideas,” in Aspects of Medieval and Renaissance Music: A Birthday Offering to Gustave Reese, ed. Jan LaRue (W. W. Norton, 1966), 29.  | 
		
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			 B:  | 
			
			 Bowles, Edmund A. “The Symbolism of the Organ in the Middle Ages: A Study in the History of Ideas.” In Aspects of Medieval and Renaissance Music: A Birthday Offering to Gustave Reese, edited by Jan LaRue, 27–39. W. W. Norton, 1966.  |