Lo, C. P. 1939- Concepts and techniques of geographic information systems / C. P. Lo and Albert W. K. Yeung - 2nd ed. - New Delhi : PHI Learning, c2009 - xii, 532 p. : ill. (some col.) ; 28 cm. ISBN: 9788120339149 Rs.450.00 (pbk.) Subjects--Topical Terms: Geographic information systems Dewey Class. No.: 910.2