call sign frequency city of license licensee format
call sign
frequency
city of license
licensee
format
number
address
list length
text unitnum address text <f,text>
kmsa 91.3 fm grand junction colorado mesa university aaa
which cities have at least three call signs ?
WDT NNS VBD-AUX IN JJS CD NN NNS .
Grand Junction
select c3 from w group by c3 having count ( c1 ) >= 3