Update index.md

Author: CelestialCalculations

index.md

@@ -2,7 +2,7 @@ The software and data provided in this GitHub repository are for the book [*Cele
 
 The software and data in this repository are provided on an as-is basis with no warranty implied or expressed. The software in this repository is copyrighted. You may copy the software and data to your computer, make backup copies, and modify the software for your personal use. You may not redistribute the original software or derivatives thereof without express permission from The MIT Press.
 
-Read endorsements for the book and purchase it from MIT Press at [https://mitpress.mit.edu/books/celestial-calculations](https://mitpress.mit.edu/books/celestial-calculations).
+Read endorsements for [*Celestial Calculations*](https://mitpress.mit.edu/books/celestial-calculations) and purchase it from MIT Press at [https://mitpress.mit.edu/books/celestial-calculations](https://mitpress.mit.edu/books/celestial-calculations).
 
 Click on the following links for more information.