Section 16. Any paper or document which is required by this chapter to be filed with or submitted to the city or town clerk or a city council or a board of selectmen shall be deemed to be so filed or submitted when it is delivered to the city or town clerk or to his office. Any paper or document which is required by this chapter to be filed with or submitted to a board of registrars of voters shall be deemed to be so filed or submitted when it is delivered to the office of the board or, if the board maintains no office, to the office of the city or town clerk. Any paper or document which is required by this chapter to be filed with or submitted to the attorney general shall be deemed to be so filed or submitted when it is delivered to the attorney general or to his office. Any paper or document which is required by this chapter to be filed with or submitted to the department of housing and community development shall be deemed to be so filed or submitted when it is delivered to said department. Any paper or document which is required by this chapter to be filed with or submitted to the state secretary shall be deemed to be so filed or submitted when it is delivered to the state secretary or to his office.