Deletion of Group urban

Comment: per nom and . I've looked at the three references we can access and they all seem to be talking about urban groups in different senses (and one is a tertiary source, an encyclopedia, which may not be considered a reliable source.) I'll keep a watch on this, but I don't know that we have a distinct concept here
Stance: delete
Cited policy: Wikipedia:No original research (WP:SYNTH)