File talk:Lithuanian language in the 16th century.png

What is the source for the map? How does it match any wikipedia criteria. IF you look a real historical document, 1528 GDL army census, you will see that border between slavic baltic language should be closer to Vilnus than the modern border. Most of soldiers from Ashmiany, Grodno, Lida have slavic Names Lastnames, but on this map those areas are "areas where lithuanian was dominant"