D. Service. Appellant(s) shall serve copies of the appeal by certified or registered mail or by personal service upon the Board at its official office and, unless named as the appellant, the Board of County Commissioners of Adams County, and upon the respondent owner(s) of the real estate at said owner's last known address. Within ten (10) days after the filing of the Real Estate Tax Assessment Appeal the Appellant(s) shall file a proof of such service with the Prothonotary. Comment: It is suggested, but not required, that the Appellant(s) provide service of the appeal upon the legislative governing body of the municipality and the board of school directors of the school district wherein the real estate is located at their respective official offices, or in the absence of any official office, at the last known address of the secretary of said body.