After the filing of said petition, and upon request therefor by the petitioners, the chancellor shall set a day certain, either in term time or in vacation, for the hearing of such petition and notice shall be given to all persons interested in, affected by, or having objections to the proposed incorporation, that the hearing on the petition will be held on the day fixed by the chancellor and that all such persons will have the right to appear and enter their objections, if any, to the proposed incorporation. The said notice shall be given by publication thereof in some newspaper published or having a general circulation in the territory proposed to be incorporated once each week for three consecutive weeks, and by posting a copy of such notice in three or more public places in such territory. The first publication of such notice and the posted notice shall be made at least thirty days prior to the day fixed for the hearing of said petition, and such notice shall contain a full description of the territory proposed to be incorporated. However, if any of the territory proposed to be incorporated is located within three miles of the boundaries of an existing municipality, then such existing municipality shall be made a party defendant to such petition and shall be served with process in the manner provided by law, which process shall be served at least thirty days prior to the date set for the hearing.