Section 6. Any city or town seeking to receive transportation service from the authority, may place upon the official ballot at any biennial or regular or special city election or annual or special town election the following question:

Yes: _______________ No: _______________.

Such question shall not be placed upon the official ballot unless the city council or town meeting shall have voted to have such question so placed or unless a petition signed by not less than 5 per cent of the registered voters of the city or town, certified as such by the registrars of voters thereof, shall have been filed with the city or town clerk, at least 90 days before the date of any such election. Forms for such petitions shall be made available without cost by the city or town clerk and each form shall bear the following heading:

''The undersigned registered voters of the (city, town) hereby petition for the placement upon the official ballot of the question whether this (city, town) shall be added to the Massachusetts Bay Transportation Area''.

The votes upon such question shall be counted and returned to the city or town clerk in the same manner as votes for candidates in municipal elections. Said clerk shall forthwith notify the authority of the results of the vote. If a majority of the votes cast upon the question shall be in the affirmative, the city or town shall be deemed to be added to the authority effective on the first day of January next following the notification by the clerk. If the city council or town meeting of more than one city or town shall vote to have such question placed on the official ballot, or if a petition signed as provided in this section shall be filed with more than one city or town clerk, and if such combination of cities or towns, if regarded as a single municipality, would be contiguous to the area constituting the authority, such question shall be placed upon the official ballot in each such city or town. The votes upon such questions shall be counted and returned to each city or town clerk in the same manner as votes for candidates in municipal elections. The city or town clerks for each said city or town shall forthwith notify the authority of the result of its vote. If a majority of the votes cast upon the vote in each city or town shall be in the affirmative, each said city or town shall be deemed to be within the authority effective on the first day of January next following the notifications by the clerks. The authority may not provide service to a city or town that fails to join the transportation area, unless such city or town was receiving service as of July 1, 2000.