In the rich text editor:
@ccott4ge
In a comment:
[ccott4ge](https://chowlings.com/user/ccott4ge)
For Names and Avatars:
In the rich text editor:
%ccott4ge
In a comment:
[![ccott4ge's Avatar](https://chowlings.com/images/avatars/default.jpg)](https://chowlings.com/user/ccott4ge) [ccott4ge](https://chowlings.com/user/ccott4ge)