Fond de carte : http://www2.demis.nl/mapserver/mapper.asp[失效链接] (mention : Disclaimer: With this statement DEMIS BV grants you permission to freely copy the PNG images returned by our server and use them for your own purposes, including web pages. We would appreciate a reference to our server but such a reference is not required, nor do we take responsibility for the accuracy or quality of the maps. sur la page http://www2.demis.nl/mapserver/DataSrc.htm)