The Text
The President or Vice-President may be removed from office in accordance with the provisions of this section. Whenever a notice of any allegation in writing signed by not less than one-third of the members of the National Assembly is presented to the President of the Senate stating that the holder of the office of President or Vice-President is guilty of gross misconduct in the performance of the functions of his office...
Source · Constitution of the Federal Republic of Nigeria, 1999, as amended · §143