Handbook on geographic information systems and digital mapping / 
Department of Economic and Social Affairs. Statistics Division. 
 - New York :  United Nations ,  2000. 
 - 197 p. 
 - ST/ESA/STAT/SER.F  79 .
<br/><br/><label>ISBN: </label>92-1-161426-0 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Geographic information systems