Every person, claiming a lien under the provisions of sections 57-801 to 57-820, shall file in the office of the county clerk for the county in which the land identified with the leasehold interest, or pipeline, or some part thereof, is situated, a statement verified by an affidavit. This statement shall set forth the amount claimed and the items thereof, the dates on which labor was performed or material or services furnished, the name of the owner or owners of the leasehold interest or pipeline, if known, the name of the claimant and his mailing address, a description of the leasehold interest or pipeline, and if the claimant be a claimant under the provisions of section 57-804, the name of the person for whom the labor was immediately performed or the material or services were immediately furnished. The statement of lien must be filed within four months after the date on which the claimant's labor was last performed or his material or services were last furnished under a single contract as provided for in section 57-810.