diff --git a/Dev-Notes.md b/Dev-Notes.md
index 2d77da3..013ac57 100644
--- a/Dev-Notes.md
+++ b/Dev-Notes.md
@@ -49,6 +49,11 @@ Elevation data tutorials/resources:
 
 3D maps need to be in a "projected" geography like Mercator, not spheroid like WGS-84.
 
+OpenGML model resources (for rendering buildings):
+
+- https://github.com/opencitymodel/opencitymodel - contains datasets by state/county
+- https://medium.com/the-pointscene-diaries/qgis-3d-buildings-tutorial-1e0111fcd766 (how to use/show CityGML in QGIS)
+
 ## 20240117
 
 Example SQL query to create a `qgis_friendly` view that converts Cayenne GPS location into PostGIS point, includes unique ID, RSSI, time, and gatewayId, and filters on gatewayId: