Programme on exchange and transfer of information  /International reference centre for community water supply and sanitation 

 - Paris:   United Nations Educational Scientific and Cultural Organization  1981 
 - 337p. 
<br/><br/>Vol.1 (Poetri reference manual) 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Information
<br/><br/><label>Subjects--Index Terms: </label>Manual