Said notice shall be published for at least three successive weeks, prior to the day set for the hearing in one newspaper published in each county in which said lands, or any part thereof within said district are situated (and if no newspaper is published in said county, in some newspaper of general circulation in the district), and by serving a copy of such notice on each of the persons, or corporations, by said report recommended to be assessed, or whose lands are by said report recommended to be included in said district, and who reside in any of the counties out of which the proposed district is formed, at least 20 days before the day of hearing in the same manner that a summons is required to be served, provided, absence from the county of such person or corporation shall excuse personal service, whereupon due publication of such notice shall be sufficient service.