An Introduction to Geographical Information Systems / 
Ian Heywood , Sarah Cornelius, Steve Carver. 
 - 3rd ed. 
 - Harlow Englang :  Pearson Prentice Hall,  2006. 
 - xxxiii,426 p,;  color ill. 
<br/><br/><label>ISBN: </label>0131293176 
<br/><br/><label>LC Class. No.: </label>G70.212  / .H49 2006