Lengyel Peter <br/><br/>
Approaches to the science of social-economic development / 
Lengyel Peter. 
 - Paris:  unesco,  1971. 
 - 383 p. :  ill. : 
<br/><br/> Includes bibliography 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Manufacturing and transport engineering <br/>Economics