update readme

README.md

@@ -5,12 +5,12 @@ Collection of password hashing algorithms, otherwise known as password-based key
 ## Supported algorithms
 
 | Algorithm | Crate | Crates.io  | Documentation | MSRV |
-|-----------|-------|------------|---------------|------|
-| [Argon2](https://en.wikipedia.org/wiki/Argon2) | `argon2` | [![crates.io](https://img.shields.io/crates/v/argon2.svg)](https://crates.io/crates/argon2) | [![Documentation](https://docs.rs/argon2/badge.svg)](https://docs.rs/argon2) | ![Minimum Supported Rust Version][msrv-1.51] |
-| [bcrypt-pbkdf](https://flak.tedunangst.com/post/bcrypt-pbkdf) | `bcrypt-pbkdf` |[![crates.io](https://img.shields.io/crates/v/bcrypt-pbkdf.svg)](https://crates.io/crates/bcrypt-pbkdf) | [![Documentation](https://docs.rs/bcrypt-pbkdf/badge.svg)](https://docs.rs/bcrypt-pbkdf) | ![Minimum Supported Rust Version][msrv-1.51] |
-| [PBKDF2](https://en.wikipedia.org/wiki/PBKDF2) | `pbkdf2` | [![crates.io](https://img.shields.io/crates/v/pbkdf2.svg)](https://crates.io/crates/pbkdf2) | [![Documentation](https://docs.rs/pbkdf2/badge.svg)](https://docs.rs/pbkdf2) | ![Minimum Supported Rust Version][msrv-1.51] |
-| [scrypt](https://en.wikipedia.org/wiki/Scrypt) | `scrypt` | [![crates.io](https://img.shields.io/crates/v/scrypt.svg)](https://crates.io/crates/scrypt) | [![Documentation](https://docs.rs/scrypt/badge.svg)](https://docs.rs/scrypt) | ![Minimum Supported Rust Version][msrv-1.51] |
-| [SHA-crypt](https://www.akkadia.org/drepper/SHA-crypt.txt) | `sha-crypt` | [![crates.io](https://img.shields.io/crates/v/sha-crypt.svg)](https://crates.io/crates/sha-crypt) | [![Documentation](https://docs.rs/sha-crypt/badge.svg)](https://docs.rs/sha-crypt) | ![Minimum Supported Rust Version][msrv-1.51] |
+|-----------|-------|:----------:|:-------------:|:----:|
+| [Argon2] | `argon2` | [![crates.io](https://img.shields.io/crates/v/argon2.svg)](https://crates.io/crates/argon2) | [![Documentation](https://docs.rs/argon2/badge.svg)](https://docs.rs/argon2) | ![MSRV 1.51][msrv-1.51] |
+| [bcrypt-pbkdf] | `bcrypt-pbkdf` |[![crates.io](https://img.shields.io/crates/v/bcrypt-pbkdf.svg)](https://crates.io/crates/bcrypt-pbkdf) | [![Documentation](https://docs.rs/bcrypt-pbkdf/badge.svg)](https://docs.rs/bcrypt-pbkdf) | ![MSRV 1.51][msrv-1.51] |
+| [PBKDF2] | `pbkdf2` | [![crates.io](https://img.shields.io/crates/v/pbkdf2.svg)](https://crates.io/crates/pbkdf2) | [![Documentation](https://docs.rs/pbkdf2/badge.svg)](https://docs.rs/pbkdf2) | ![MSRV 1.51][msrv-1.51] |
+| [scrypt] | `scrypt` | [![crates.io](https://img.shields.io/crates/v/scrypt.svg)](https://crates.io/crates/scrypt) | [![Documentation](https://docs.rs/scrypt/badge.svg)](https://docs.rs/scrypt) | ![MSRV 1.51][msrv-1.51] |
+| [SHA-crypt] | `sha-crypt` | [![crates.io](https://img.shields.io/crates/v/sha-crypt.svg)](https://crates.io/crates/sha-crypt) | [![Documentation](https://docs.rs/sha-crypt/badge.svg)](https://docs.rs/sha-crypt) | ![MSRV 1.51][msrv-1.51] |
 
 Please see the [OWASP Password Storage Cheat Sheet] for assistance in selecting an appropriate algorithm for your use case.
 
@@ -41,4 +41,9 @@ Unless you explicitly state otherwise, any contribution intentionally submitted
 
 [//]: # (general links)
 
+[Argon2]: https://en.wikipedia.org/wiki/Argon2
+[bcrypt-pbkdf]: https://flak.tedunangst.com/post/bcrypt-pbkdf
+[PBKDF2]: https://en.wikipedia.org/wiki/PBKDF2
+[scrypt]: https://en.wikipedia.org/wiki/Scrypt
+[SHA-crypt]: https://www.akkadia.org/drepper/SHA-crypt.txt
 [OWASP Password Storage Cheat Sheet]: https://cheatsheetseries.owasp.org/cheatsheets/Password_Storage_Cheat_Sheet.html