Cathedral, forge, and waterwheel : technology and invention in the middle ages 
Gies, Frances. 
 -  Harper Collins Publishers,  1994 
 - 357 p. 
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<br/><br/><label>ISBN: </label>0-06-016590-1 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Invention -- History.
<br/><br/><label>Dewey Class. No.: </label>609.40902 G455 1994