Section 6 in The Calcutta Municipal Corporation Act, 1980
6. Election of Mayor and Chairman. -
The elected members of the Corporation shall elect from amongst themselves, -(a)at the first meeting of the Corporation after a general election,-(i)one member to be the Mayor, and(ii)one member to be the Chairman, and(b)so often as a vacancy in the office of the Mayor or the Chairman, as the case may be, occurs by reason of death, resignation, removal or otherwise and within one month of the occurrence of such vacancy, one member to be the Mayor or the Chairman, as the case may be, who shall assume office forthwith after taking such oath of secrecy as may be prescribed.
