00320nam a2200109Ia 4500008004100000020002200041040002900063050002400092100002100116245005100137260002200188221216s9999||||xx |||||||||||||| ||und||  a978-0-19-823365-7  cChuka University Library  aG 70.21b .B87 1998  aBurrough,Peter A 0aPrinciples of geographical information systems  aOUPbOxfordc1998