https://gis.stackexchange.com/questions/8650/measuring-accuracy-of-latitude-and-longitude
https://gis.stackexchange.com/questions/664/difference-between-projection-and-datum
https://gis.stackexchange.com/questions/5701/differences-between-dem-dsm-and-dtm
https://gis.stackexchange.com/questions/3083/seeking-examples-of-beautiful-maps
https://gis.stackexchange.com/questions/5068/how-to-create-an-accurate-tissot-indicatrix
https://gis.stackexchange.com/questions/25494/how-accurate-is-approximating-the-earth-as-a-sphere
https://gis.stackexchange.com/questions/7839/identifying-coordinate-system-of-shapefile-when-unknown
https://gis.stackexchange.com/questions/5821/calculating-latitude-longitude-x-miles-from-point
https://gis.stackexchange.com/questions/31701/calculating-areal-distortion-outside-utm-zone
https://gis.stackexchange.com/questions/53728/are-ellipsoids-a-mathematical-necessity
https://gis.stackexchange.com/questions/25982/geodetic-coordinates-and-latitude-longitude
https://gis.stackexchange.com/questions/75528/understanding-terms-in-length-of-degree-formula
https://gis.stackexchange.com/questions/25528/how-much-water-on-earthusgs-a-wrong-map-representation
https://gis.stackexchange.com/questions/122703/influence-of-the-scale-factor-on-the-projection