26 U.S.C. § 7807 — Rules in effect upon enactment of this title

(a) Interim provision for administration of title Until regulations are promulgated under any provision of this title which depends for its application upon the promulgation of regulations (or which is to be applied in such manner as may be prescribed by regulations) all instructions, rules or regulations which are in effect immediately before the enactment of this title must, to the extent such instructions, rules, or regulations could be prescribed as regulations under authority of such provision, be applied as if promulgated as regulations under such provision. (b) Provisions of this title corresponding to prior internal revenue laws (1) Reference to law applicable to prior period Any provision of this title which refers to the application of any portion of this title to a prior period (or which depends upon the application to a prior period of any portion of this title) must, when appropriate and consistent with the purpose of such provision, be deemed to refer to (or depend upon the application of) the corresponding provision of the Internal Revenue Code of 1939^* or of such other internal revenue laws as were applicable to the prior period. (2) Elections or other acts If an election or other act under the provisions of the Internal Revenue Code of 1939 would, if this title had not been enacted, be given effect for a period after the date of enactment of this title, and if corresponding provisions are contained in this title, such election or other act is given effect under the corresponding provisions of this title.