Section 147(2) in The Representation of the People Act, 1951
(2)As soon as may be after the date of commencement of the Constitution (Seventh Amendment) Act, 1956, bye-elections shall be held to fill the vacancies existing on that date in the seats allotted to the States of Assam, Orissa and Uttar Pradesh and the Union territories of Delhi, Himachal Pradesh and Manipur.
