I was wondering if anyone has made a datatype that I can use on a page that lets the editor select a group of members?

What I want to do is make a site for my sports club. I've come up with this structure:

Frontpage
- Basketball (department)
- - Mens team (team)
- - Ladies team (team)
- Soccer (department)
- - Mens team 1 (team)
...and so on.

On my (team) document type, I'd like to be able to select which group of members to display on the team page as the team members. I guess this could be done udsing just a text field, and type in the name of the group, but that is just not going to work :-)

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