An introduction to geographical information systems / 
Ian Heywood ... [et.al] 
 - 3rd ed. 
 - Harlow :   Pearson Prentice Hall,   2006. 
 - xxxiii, 426 p. :   ill. ;   27 cm. 
<br/><br/>Includes bibliographical references (p. 399-411) and index. 
<br/><br/><label>ISBN: </label>0131293176 
<br/><br/><label>Subjects--Topical Terms: </label><br/> Geographic information systems.
<br/><br/><label>Dewey Class. No.: </label>910.285