Thailand province map source and attribution

Source: geoBoundaries gbOpen THA ADM1, boundaryID THA-ADM1-36821470.
Boundaries represent 2017. Data provider: OpenStreetMap / Wambacher.
API: https://www.geoboundaries.org/api/current/gbOpen/THA/ADM1/
Original simplified GeoJSON (commit 9469f09):
https://media.githubusercontent.com/media/wmgeolab/geoBoundaries/9469f09/releaseData/gbOpen/THA/ADM1/geoBoundaries-THA-ADM1_simplified.geojson
License: Open Data Commons Open Database License 1.0 (ODbL).
https://opendatacommons.org/licenses/odbl/1-0/
https://www.openstreetmap.org/copyright
Copyright OpenStreetMap contributors. Credit geoBoundaries.

The original simplified GeoJSON is available alongside this file at
thailand-provinces.geojson under its original ODbL license.
KhumInsure's derived six-region grouping and SVG geometry are available at
thailand-region-map.json under ODbL 1.0; attribution above must be retained.
The display uses a local equirectangular projection (horizontal scale 39,
vertical scale 40), with geographic north at the top. This is a navigation
map, not a road map, cadastral survey or hospital point-location map.
Six geographical groups are used for browsing, not health service zones.
Colors distinguish groups only; counts refer solely to listed hospitals.