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@@ -351,6 +351,7 @@ For a list of free machine learning books available for download, go [here](http
 * [simple-statistics](https://github.com/tmcw/simple-statistics) - A JavaScript implementation of descriptive, regression, and inference statistics. Implemented in literate JavaScript with no dependencies, designed to work in all modern browsers (including IE) as well as in node.js.
 * [regression-js](https://github.com/Tom-Alexander/regression-js) - A javascript library containing a collection of least squares fitting methods for finding a trend in a set of data.
 * [Lyric](https://github.com/flurry/Lyric) - Linear Regression library.
+* [GreatCircle](https://github.com/mwgg/GreatCircle) - Library for calculating great circle distance.
 
 <a name="julia" />
 ## Julia
@@ -691,6 +692,7 @@ on MNIST digits[DEEP LEARNING]
 * [Allen Downey’s Think Complexity Code](https://github.com/AllenDowney/ThinkComplexity) - Code for Allen Downey's book Think Complexity.
 * [Allen Downey’s Think OS Code](https://github.com/AllenDowney/ThinkOS) - Text and supporting code for Think OS: A Brief Introduction to Operating Systems.
 * [Python Programming for the Humanities](http://fbkarsdorp.github.io/python-course/) - Course for Python programming for the Humanities, assuming no prior knowledge. Heavy focus on text processing / NLP.
+* [GreatCircle](https://github.com/mwgg/GreatCircle) - Library for calculating great circle distance.
 
 <a name="python-kaggle" />
 #### Kaggle Competition Source Code