Dudley Station Map by Sky Rose is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License with the following additions:
You are free to use, distribute, and modify this work for private or public, but not commercial, uses, so long as you leave credit in the work itself (i.e. in the image, not as a caption). I'd love to see your remix.
MBTA, if you're reading this, I'd love to have this used officially, but talk to me first.