Update docs/book/index.md

Author: rickecon

docs/book/index.md

@@ -36,7 +36,7 @@ Put here a description of the code and tests available in the repository.
 Please use the following citation form for this book.
 
 General citation to the book:
-* Evans, Richard W., *Computational Methods for Economists using Python*, Open access Jupyter Book, v#.#.#, 2023, [url to book].
+* Evans, Richard W., *Computational Methods for Economists using Python*, Open access Jupyter Book, v#.#.#, 2023, https://opensourceecon.github.io/CompMethods.
 
 Citation to a chapter in the book:
-* Evans, Richard W., "[insert chapter name]", in *Computational Methods for Economists using Python*, Open access Jupyter Book, v#.#.#, 2023, [url to chapter].
+* Evans, Richard W., "[insert chapter name]", in *Computational Methods for Economists using Python*, Open access Jupyter Book, v#.#.#, 2023, https://opensourceecon.github.io/CompMethods + [chapter path].