diff --git a/books/free-programming-books-langs.md b/books/free-programming-books-langs.md
index 20500cc43..f6203bfd1 100644
--- a/books/free-programming-books-langs.md
+++ b/books/free-programming-books-langs.md
@@ -505,6 +505,7 @@ Books on general-purpose programming that don't focus on a specific language are
 * [.NET Book Zero](http://www.charlespetzold.com/dotnet) - Charles Petzold (PDF, XPS)
 * [.NET Microservices: Architecture for Containerized .NET Applications](https://dotnet.microsoft.com/download/e-book/microservices-architecture/pdf) - Cesar de la Torre, Bill Wagner, Mike Rousos (PDF)
 * [Porting Existing ASP.NET Apps to .NET 6](https://docs.microsoft.com/en-us/dotnet/architecture/porting-existing-aspnet-apps/) - Steve "ardalis" Smith
+* [Programming Basics with C#](https://csharp-book.softuni.org) - Svetlin Nakov et al. (HTML, PDF, EPUB)
 * [Threading in C#](http://www.albahari.com/threading/)
 * [Xamarin Community Toolkit Succinctly](https://www.syncfusion.com/succinctly-free-ebooks/xamarin-community-toolkit-succinctly) - Alessandro Del Sole
 * [Xamarin.Forms for macOS Succinctly](https://www.syncfusion.com/ebooks/xamarin_forms_for_mac_os_succinctly) - Alessandro Del Sole