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@@ -194,6 +194,12 @@ Full reference, architecture notes, and algorithmic detail in the [wiki](https:/
 
 ---
 
+## Acknowledgments
+
+Calendar data and algorithms provided by [hijri-core](https://github.com/acamarata/hijri-core). The Umm al-Qura table is derived from data published by the King Abdulaziz City for Science and Technology (KACST). FCNA new moon calculations follow Jean Meeus, "Astronomical Algorithms," 2nd ed., Chapter 49.
+
+---
+
 ## License
 
 MIT. Copyright (c) 2026 Aric Camarata. See [LICENSE](LICENSE).