diff --git a/Projektarbeit-3.md b/Projektarbeit-3.md
index 5e42b20..a87819c 100644
--- a/Projektarbeit-3.md
+++ b/Projektarbeit-3.md
@@ -8,6 +8,13 @@ Referenz:
 
 Frontend:
 * https://docs.mapbox.com/mapbox-gl-js/example/
+* https://apexcharts.com/angular-chart-demos/
+* https://www.digitalocean.com/community/tutorials/angular-angular-and-leaflet
+* https://angular.io/guide/router
+* https://getbootstrap.com/docs/4.0/layout/grid/
+* https://material.angular.io/components/categories
+* https://materialtheme.arcsine.dev/
+* https://www.patrick-wied.at/static/heatmapjs/?utm_source=npm_leaflet&utm_medium=web
 
 Backend
 * https://cycling.data.tfl.gov.uk