The coordinates used in the village database come from this map www.lib.utexas.edu/maps/ams/china/txu-oclc-10552568-nf49-8.jpg (clicking the hyperlink doesn't work, you'll need to copy and paste the link). This map is quite old (compiled in 1954) and the English transcriptions are in Wade Giles so it can be confusing to many users. Nonetheless, it is still very useful as a guide since there isn't much difference in the names of individual villages between this map and a modern map.