What are the names of teams from universities that have a below average enrollment?
SELECT t2.team_name FROM university AS t1 JOIN basketball_match AS t2 ON t1.school_id  =  t2.school_id WHERE enrollment  <  (SELECT avg(enrollment) FROM university)
Ortalamanın altında bir kaydı olan üniversitelerden gelen takımların isimleri nelerdir?