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@@ -470,6 +470,8 @@ On-line courses, blog posts, and reports related to open transit data.
 - [Open Transit Data Toolkit](http://transitdatatoolkit.com/) - A series of lessons to help people utilize open transit data.
 - [MBTA GTFS Onboarding](https://mybinder.org/v2/gh/mbta/gtfs_onboarding/main?urlpath=lab/tree/GTFS_Onboarding.ipynb) - An interactive tutorial created by MBTA for GTFS static. A [stand-alone Docker image](https://github.com/mbta/gtfs_onboarding) is available on GitHub as well as a [hosted/no-install version](https://mybinder.org/v2/gh/mbta/gtfs_onboarding/main?urlpath=lab/tree/GTFS_Onboarding.ipynb) of the Jupyter notebook.
 - [Planetizen "Building a Transit Map Web App" course](https://courses.planetizen.com/course/building-transit-map-app) - A video tutorial on setting up your own web-based mapping application, with no coding experience required. 
+- [GTFS-books](https://github.com/MobilityData/GTFS-books) - Comprehensive guides to GTFS and GTFS Realtime. These books were written by [Quentin Zervaas](https://github.com/HendX), and have been donated to [MobilityData](https://mobilitydata.org/) and made open access.
+
 
 #### Blog posts