Records and statements.

Every person upon whom the duty is imposed by this chapter to file any applications, returns, or reports or who is liable for any tax imposed by this chapter shall keep such records, render under oath such statements, and comply with such rules and regulations as the Mayor from time to time may prescribe. Whenever the Mayor deems it necessary, he may require any person, by notice served upon him, to make a return, render under oath such statements, or keep such records as he believes sufficient to show whether or not such person is liable to tax under this chapter and the extent of such liability.