United Nations. <br/><br/>
Variations in the incidence of knowledge and use of contraception: A comparative analysis. 

 - New York :  UN,  1981. 
<br/><br/> Gives a comparative analyses of world fertility survey results for twenty developing countries. 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Family Planning.<br/>Developing countries -- Contraception.--Developing countries -- Contraception.