Mansfield, Edwin. <br/><br/>
The economics of technological change. 

 - [London] :  Longmans,  [1969] 
<br/><br/>Bibliographical footnotes. 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Technological innovations -- United States.--Technological innovations -- United States.<br/>Research, Industrial -- United States.--Research, Industrial -- United States.