In the geo temporal map view, you get a quick visual impression of the geographical location of the sources that came up in your search, as well as a timeline visualization of these same sources. Note that the geographical locations are not necessarily where the sources were produced. We strive to add geographical data for both production and holding location, but this is not always possible. Currently, we show the holding location on the map. Also note that locations for which the location is unknown are not shown on the map.
Similarly, the timeline only includes sources for which a date / year is available. Furthermore, if a source is dated to a period (e.g. 'ca. 1450 - 1456') the first date mentioned is used (i.e. 1450).