Inventors and discoverers :  changing our worlsd  -- Wasington, D.C.  National Geographic Book Service  1988 <br/>320 p.:  ill. ;  28 cm. <br/><br/> Includes index. <br/><br/><label>ISBN: </label>0-87044-752-1 <br/><br/><label>Subjects--Topical Terms: </label><br/>Inventions-History.<br/><br/><label>Dewey Class. No.: </label>GR 609 I622 1988