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index.md

@@ -216,7 +216,7 @@ presentation of the maths".
 ### Books
   - [Cakes, Custard and Category Theory: Easy recipes for understanding complex maths](http://www.amazon.com/Cakes-Custard-Category-Theory-understanding-ebook/dp/B00TA8SIV6) — [Eugenia Cheng](http://eugeniacheng.com/)
   - Category Theory, Steve Awodey. [pdf](https://pages.jh.edu/rrynasi1/NewFoundations4Math/Literature/Textbooks/Awodey2010CategoryTheory.2ndEdition.pdf) [course](https://pages.jh.edu/rrynasi1/NewFoundations4Math/Literature/Textbooks/Awodey2016CategoryTheory.LectureNotes/)
-  - Basic Category Theory for Computer Scientists - Benjamin C. Pierce. Previously available in a draft entitled [A taste of category theory for computer scientists](http://repository.cmu.edu/cgi/viewcontent.cgi?article=2846&context=compsci)
+  - Basic Category Theory for Computer Scientists - Benjamin C. Pierce. Previously available in a draft entitled [A taste of category theory for computer scientists](https://kilthub.cmu.edu/articles/journal_contribution/A_taste_of_category_theory_for_computer_scientists/6602756/1)
   - [Categories for the Working Mathematician](http://www.mtm.ufsc.br/~ebatista/2016-2/maclanecat.pdf) — Saunders Mac Lane
   - [Conceptual Mathematics](http://www.cambridge.org/us/academic/subjects/mathematics/logic-categories-and-sets/conceptual-mathematics-first-introduction-categories-2nd-edition) A First Introduction to Categories, 2nd Edition - F. William Lawere and Stephen H. Schanuel
   - [Category Theory for the Sciences](http://category-theory.mitpress.mit.edu/) — David I. Spivak. Previously available in a draft entitled [Category Theory for Scientists](http://math.mit.edu/~dspivak/CT4S.pdf)