3T Devogele, C Parent , S Spaccapietra. On spatial Database intergration [J].International Journal of Geograhica Information Science, 1998,12 (4):335~352.
4Loucopoulos P .Zicari R. An integrated View of information system development , conceptual modling , database and case[M]. New York :John Wiley&Sons, 1992.