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 - [Simple Comic](https://apps.apple.com/us/app/simple-comic/id1497435571?mt=12) - Reader for PDF, CBZ, and CBR formats. 🍎
 
 ### PDF Tools
-- [Sumatra PDF](https://sumatrapdfreader.org/free-pdf-reader) - Fast, lightweight PDF reader. 🪟 ⭐
+
+- [Sumatra PDF](https://sumatrapdfreader.org/free-pdf-reader) - Fast, lightweight PDF reader. 🪟 [🟢](https://github.com/sumatrapdfreader/sumatrapdf) ⭐
 - [Foxit PDF Reader](https://foxit.com/pdf-reader/) - PDF viewer with annotations. 🪟 🍎
-- [MuPDF](https://mupdf.com/) - Powerful PDF viewer. 🪟 🐧 🟢
-- [Okular](https://okular.kde.org/) - Universal document viewer by KDE. 🪟 🍎 🐧
-- [PDF Arranger](https://github.com/pdfarranger/pdfarranger) - PDF editor for splitting, merging. 🪟 🐧 🟢
+- [MuPDF](https://mupdf.com/) - Powerful PDF viewer. 🪟 🐧 [🟢](https://github.com/ArtifexSoftware/mupdf)
+- [Okular](https://okular.kde.org/) - Universal document viewer by KDE. 🪟 🍎 🐧 [🟢](https://github.com/KDE/okular)
+- [PDF Arranger](https://github.com/pdfarranger/pdfarranger) - PDF editor for splitting, merging. 🪟 🐧 [🟢](https://github.com/pdfarranger/pdfarranger)
 - [PDF24](https://pdf24.org/en/) - Easy PDF tools. 🪟
-- [qpdfview](https://launchpad.net/qpdfview) - Tabbed document viewer. 🐧
-- [Skim](https://skim-app.sourceforge.io/) - PDF viewer for annotation. 🍎
-- [Xournal++](https://xournalpp.github.io/) - Handwriting and annotation tool for PDFs. 🪟 🍎 🐧
+- [qpdfview](https://launchpad.net/qpdfview) - Tabbed document viewer. 🐧 [🟢](https://github.com/bendikro/qpdfview)
+- [Skim](https://skim-app.sourceforge.io/) - PDF viewer for annotation. 🍎 [🟢](https://github.com/JackieXie168/skim)
+- [Xournal++](https://xournalpp.github.io/) - Handwriting and annotation tool for PDFs. 🪟 🍎 🐧 [🟢](https://github.com/xournalpp/xournalpp/)
 
 ## Note Taking