Frances Gies. <br/><br/>
Cathedral, forge, and  waterwheel: Technology and invention in the middle ages. 

 - 1st ed. 
 - 10 East 53rd street, New York.  Harper Collins publishers  1994 
 - 357p. 
<br/><br/><label>ISBN: </label>0060165901 
<br/><br/><label>Subjects--Topical Terms: </label><br/>1. Technology--History. 2. Inventions--History
<br/><br/><label>LC Class. No.: </label>T 17 .G54 1994.