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