law: The Income-Tax Act, 1961
  29. Income from profits and gains of business or profession, how computed.-
  The income referred to in section 28 shall be computed in accordance with the provisions contained in sections 30 to 1[43D].
  1. Subs. by Act 49 of 1991, s. 10, for "43C" (w.e.f. 1-4-1992).