README.md in trackler-2.2.1.55

- old
+ new
@@ -24,20 +24,21 @@
 pass, remove the ignore flag (`#[ignore]`) from the next test and get the tests
 to pass again.  The test file is located in the `tests` directory.   You can
 also remove the ignore flag from all the tests to get them to run all at once
 if you wish.
 
-Make sure to read the [Crates and Modules](https://doc.rust-lang.org/stable/book/crates-and-modules.html) chapter if you
+Make sure to read the [Modules](https://doc.rust-lang.org/book/second-edition/ch07-00-modules.html) chapter if you
 haven't already, it will help you with organizing your files.
 
 ## Feedback, Issues, Pull Requests
 
 The [exercism/rust](https://github.com/exercism/rust) repository on GitHub is the home for all of the Rust exercises. If you have feedback about an exercise, or want to help implement new exercises, head over there and create an issue. Members of the [rust track team](https://github.com/orgs/exercism/teams/rust) are happy to help!
 
 If you want to know more about Exercism, take a look at the [contribution guide](https://github.com/exercism/docs/blob/master/contributing-to-language-tracks/README.md).
 
 [help-page]: http://exercism.io/languages/rust
-[crates-and-modules]: http://doc.rust-lang.org/stable/book/crates-and-modules.html
+[modules]: https://doc.rust-lang.org/book/second-edition/ch07-00-modules.html
+[cargo]: https://doc.rust-lang.org/book/second-edition/ch14-00-more-about-cargo.html
 
 ## Source
 
 All of Computer Science [http://www.wolframalpha.com/examples/NumberBases.html](http://www.wolframalpha.com/examples/NumberBases.html)
 