Within Teamwork Desk, you can add new custom ticket sources in addition to the default ones available.
Click your profile icon to the right of the main navigation bar and choose Settings from the dropdown.
In the Settings area, go to the General subsection and select Ticket Types from the left sidebar menu.
You will see a list of the default ticket sources that are built into Teamwork Desk. These sources cannot be removed.
To add a custom source, add the source name into the Add ticket source field below the search bar and click Add.
The new source will be added to your list of ticket sources. Hover over the ticket source to access the edit and delete options.
When viewing tickets, you will see the new source is available in the Source dropdown under Ticket Options in the right sidebar.
Note: Only administrators on your Teamwork Desk account can add/edit or delete ticket sources.
For more information, see: Managing Site Settings