GIS : a computing perspective / Michael Worboys, Matt Duckham. Worboys, Michael. Duckham, Matt, 1972- Geographic information systems. G70.2 .W659 2004 910.285 22 WOG Includes bibliographical references (p. 391-411) and index. Boca Raton, Fla. : CRC Press, c2004. c2004. 2004 Text 426 p. : äb ill., maps ; http://www.loc.gov/catdir/toc/fy051/2004045490.html http://www.loc.gov/catdir/enhancements/fy0646/2004045490-d.html eng