CREATE TABLE table_66623 ("City of license" TEXT, "Identifier" TEXT, "Frequency" TEXT, "Power" TEXT, "Class" TEXT, "RECNet" TEXT)

What is listed for the RECNet that also has a Frequency of 91.1 FM?
SELECT "RECNet" FROM table_66623 WHERE "Frequency" = '91.1 fm'
SELECT "RECNet" FROM "table_66623" WHERE "Frequency" = '91.1 fm'