Aarssen, Lonnie William <br/><br/>
Why is fertility lower in wealthier countries? The role of relaxed fertility-selection 

 - 14 p. 
<br/><br/> gráfs. 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Paises Desarrollados<br/>Fecundidad<br/>Baja de la Fecundidad