Conn. Gen. Stat. § 7-373

Each town, city, borough, school district, fire district and sewer district and each other municipal corporation and association having a population of less than ninety thousand inhabitants as determined by the federal census last taken, which issues bonds pursuant to its general or special powers, shall, for each such issue, designate a bank or trust company incorporated under the laws of this or any other state, or of the United States, to certify such issue and shall also designate a bank or trust company incorporated under the laws of this or any other state, or of the United States, to act as disbursing agent in the payment of principal and interest on such bonds. Such certification shall be endorsed upon each bond and shall identify such bond as being one of the particular issue described in such bond, shall certify the genuineness of the signatures and seal thereto affixed, shall state the name of the attorney at law who has rendered an opinion approving the legality of such particular issue and shall be signed by an authorized officer or official of such bank or trust company.