Ehrlich, Paul R.  <br/><br/>
Population, resources, environment :  issues in human ecology / 
Paul R. Ehrlich & Anne H. Ehrlich. 
 - SECOND EDITION 
 - San Francisco, California :  W. H. Freeman and Company,  1972. 
 - 30 p. ;  24 cm. 
<br/><br/><br/>Englés 
<br/><br/><label>ISBN: </label> Normal 
<br/><br/><label>Subjects--Index Terms: </label>Conservation Conservación Natural resources Recursos naturales Ecology Ecología Education Educación 
<br/><br/><label>Dewey Class. No.: </label>333.72