Mass. Gen. Laws ch. 53 § 96
Nominations of candidates for elective city or town offices and for caucus officers to be voted for at a caucus, shall be made by nomination papers, as hereinafter provided. Such nominations shall be made on the blank nomination papers prepared and delivered in accordance with the preceding section; and no nomination paper offered for filing shall be received or shall be valid to which is attached any card, paper or other device, containing the name of a candidate, his written acceptance, or containing the signature of any voter required by this section. Such papers shall be signed in person by at least five voters of the ward or town where the caucus is to be held, and for a district composed of more than one ward shall be signed by a number of voters equal in the aggregate to not less than five voters for each ward in said district, and shall be subject to sections forty-five and sixty, except that the nomination paper of a candidate for caucus officer shall not contain the statement permitted by section forty-five. No vacancy caused by the death, withdrawal or ineligibility of any of the above candidates shall be filled, unless the person entitled to fill such vacancy files the written acceptance of the candidate nominated to fill the vacancy.
Mass. Gen. Laws ch. 53, § 96