The appointment of such committee may be by an instrument or instruments in writing, executed by the persons so holding or claiming such title and acknowledged as provided by law for acknowledgment of other interests affecting the title to real estate in this state, which instrument or instruments or certified copies thereof shall be filed at the time of commencement of such action in the office of the clerk of the district court of the district in which such tract of land is situate and the decree rendered therein shall recite the names of all such persons so participating in the selection of said committee and shall be binding upon all such persons as an adjudication of their interests in the tract of land involved. All persons claiming any interest or estate in such tract of land as tenants in common or otherwise who do not participate in the selection of such committee, and all unknown claimants thereto may be made parties defendant to such action and process may be served upon them as in other civil actions.