Such lien shall be discharged unless the person desiring to avail himself thereof, within ninety days from the time he shall have ceased to work or labor for such incorporated company or for such contractor, shall file with the clerk of the county court of the county in which such work or labor was performed, or in which the principal office, works, real estate or personal property of such incorporated company is situated, a notice of lien containing the amount due him after allowing all credits, which notice shall be sworn to by the person claiming such lien, or by someone in his behalf.