As used in the regulations in this part, unless otherwise expressly indicated:

(a) The terms defined in the provisions of law contained in the regulations in this part shall have the meanings so assigned to them.

(b) The Internal Revenue Code of 1954 means the Act approved August 16, 1954 (68A Stat.), entitled “An Act To revise the internal revenue laws of the United States”, as amended.

(c) District director means district director of internal revenue.

(d) The cross references in the regulations in this part to other portions of the regulations, when the word “see” is used, are made only for convenience and shall be given no legal effect.