All claims against the city shall be filed with the City Clerk. Every claim must be set out in detail and sworn to before any City Clerk or some other officer authorized to administer oaths, by the claimant or his authorized agent. Such affidavit shall state that the claim is just, true and correct, and that the price charged is not more than reasonable and customary, and that it has (or has not) been theretofore rejected by the Council or committee. If such claim is based upon the contract it shall be stated therein, that it is according to it, as to price, quality, quantity and kind of service performed. No claim shall be allowed or any warrant drawn for its payment unless these conditions are complied with. When material has been furnished, or work done on the order of a properly authorized officer of the city he shall certify such claim before it is filed with the City Clerk.
('68 Code, § 2.17)