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 # TeachBooks Manual
 
-This is an introduction to Git, VS Code and Jupyter Books for teachers and teaching assistants involved in TeachBooks, our platform easing the process of making a <a href="https://jupyterbook.org/"><img  style="display:inline-block; height:1.5em; width:auto; transform:translate(0, -0.15em)" src="images/logo-wide.svg" alt="Jupyter book"></a>. This book will continue to develop, so feel free to contribute https://gitlab.tudelft.nl/interactivetextbooks-citg/jupyter-book-manual! For more information about teachbooks, visit [https://teachbooks.tudelft.nl/](https://teachbooks.tudelft.nl/).
+This manual assists you in creating and collaborating on <a href="https://jupyterbook.org/"><img  style="display:inline-block; height:1.5em; width:auto; transform:translate(0, -0.15em)" src="images/logo-wide.svg" alt="Jupyter book"></a> for educational purposes. Some parts are specifically aimed for teachers at Delft University of Technology, although all material and tools are openly available. This manual aims at providing an easy start and advanced usages for new and existing users with or without skills on this topic. it is part of TeachBooks, for more information visit [https://teachbooks.tudelft.nl/](https://teachbooks.tudelft.nl/).
 
 ## Contact
 If you encounter any issues and you have a TU Delft account, report it by clicking  <svg class="svg-inline--fa fa-gitlab" aria-hidden="true" focusable="false" data-prefix="fab" data-icon="gitlab" role="img" xmlns="http://www.w3.org/2000/svg" viewBox="0 0 512 512" data-fa-i2svg=""><path fill="currentColor" d="M503.5 204.6L502.8 202.8L433.1 21.02C431.7 17.45 429.2 14.43 425.9 12.38C423.5 10.83 420.8 9.865 417.9 9.57C415 9.275 412.2 9.653 409.5 10.68C406.8 11.7 404.4 13.34 402.4 15.46C400.5 17.58 399.1 20.13 398.3 22.9L351.3 166.9H160.8L113.7 22.9C112.9 20.13 111.5 17.59 109.6 15.47C107.6 13.35 105.2 11.72 102.5 10.7C99.86 9.675 96.98 9.295 94.12 9.587C91.26 9.878 88.51 10.83 86.08 12.38C82.84 14.43 80.33 17.45 78.92 21.02L9.267 202.8L8.543 204.6C-1.484 230.8-2.72 259.6 5.023 286.6C12.77 313.5 29.07 337.3 51.47 354.2L51.74 354.4L52.33 354.8L158.3 434.3L210.9 474L242.9 498.2C246.6 500.1 251.2 502.5 255.9 502.5C260.6 502.5 265.2 500.1 268.9 498.2L300.9 474L353.5 434.3L460.2 354.4L460.5 354.1C482.9 337.2 499.2 313.5 506.1 286.6C514.7 259.6 513.5 230.8 503.5 204.6z"></path></svg> --> {fa}`lightbulb` on the top right corner of this page. Or contribute directly by creating a merge request in the [repository](https://gitlab.tudelft.nl/interactivetextbooks-citg/jupyter-book-manual).
 
 If you have questions, contact Tom van Woudenberg, Robert Lanzafame or our TA Julie Kirsch at TeachBooks@tudelft.nl, also for non-TU Delft account holders. TU Delft account holder can also contact us in the [MS Teams Open Interactive Textbooks Community](https://teams.microsoft.com/l/team/19%3Ah9-uRcP_yYauh-VuoPFozJVUvHVOB4a0mz1ZWvh4q4Q1%40thread.tacv2/conversations?groupId=3e88c1f3-4a4f-483a-a366-7e617de9ba99&tenantId=096e524d-6929-4030-8cd3-8ab42de0887b)
 
-## Feedback
 We really value your feedback on this manual. This helps us improving it. Please keep using the manual as you build your own Jupyter Book and come back to fill out this short [survey](https://forms.gle/hXbFUQgN95H8ftxt9).
 
+## Contribute
+This book will continue to develop, so feel free to contribute https://gitlab.tudelft.nl/interactivetextbooks-citg/jupyter-book-manual! You can do so directly by forking this repository and creating a merge request.
+
+The released book can be found on on https://teachbooks.tudelft.nl/jupyter-book-manual. This page shows the built book of the `release` branch. The `main` branch is meant for reviewing and is visible here: https://teachbooks.tudelft.nl/jupyter-book-manual/draft. All branches will also be visible on the mirrored repository on GitHub Pages: https://github.com/TeachBooks/mirror_teachbook_manual/actions
+
+Some parts of this book are taken from other sources in the form of submodules (linked in the folder [book/external](book/external)). To contribute to those pages, contribute to the source repository directly with a fork and merge/pull request. If you intent to clone this boko including its submodules, clone using: `git clone --recurse-submodules git@gitlab.tudelft.nl:interactivetextbooks-citg/jupyter-book-manual.git`
+
 Happy book building!
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