IX International Congress of Hygiene and Demography   : provisional programme. 

 - Madrid :   [s.n.],   1897 ( 
 - 29 p. ;   16 cm. 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Higiene---Congresos y asambleas.<br/>Demografía---Congresos y asambleas.