diff --git a/README.md b/README.md
index dc51334..80d14c4 100644
--- a/README.md
+++ b/README.md
@@ -88,7 +88,7 @@ using this library.
 
 **References**
 
-- https://github.com/arbakker/pdok-js-map-examples/blob/master/leaflet-geojson-wmts-epsg28992/index.js
+- https://github.com/arbakker/pdok-js-map-examples/blob/c9ee1c/leaflet-geojson-wmts-epsg28992/index.js
 - https://nlmaps.nl/
   https://github.com/PDOK/nlmaps/blob/cf2ba6b825853e8bfc34ed3c7b7ff779dda722e9/packages/nlmaps/test/browser-test.js#L36
 - https://github.com/geoloep/Leaflet.RD/blob/master/src/leaflet.rd.js
diff --git a/src/rd.ts b/src/rd.ts
index f572876..87291a9 100644
--- a/src/rd.ts
+++ b/src/rd.ts
@@ -7,7 +7,7 @@ import 'proj4leaflet';
  * @note
  *
  * This code is heavily inspired on
- * https://github.com/arbakker/pdok-js-map-examples/blob/master/leaflet-geojson-wmts-epsg28992/index.js,
+ * https://github.com/arbakker/pdok-js-map-examples/blob/c9ee1c/leaflet-geojson-wmts-epsg28992/index.js,
  * but there are many caveats expressed on
  * https://geoforum.nl/t/betrouwbare-bron-voor-proj4-definitie-van-rd-new-epsg-28992/5144/16.
  *
@@ -53,7 +53,7 @@ const RESOLUTIONS = [
  *
  * @see
  *
- * https://github.com/arbakker/pdok-js-map-examples/blob/master/leaflet-geojson-wmts-epsg28992/index.js
+ * https://github.com/arbakker/pdok-js-map-examples/blob/c9ee1c/leaflet-geojson-wmts-epsg28992/index.js
  */
 const RD_PROJECTION = `+proj=sterea\
 +lat_0=52.15616055555555\