Sec. 1. As used in this chapter, "income tax return" means any of the following:
(1) An individual income tax return under IC 6-3.
(2) A corporate income tax return under IC 6-3.
(3) A financial institutions tax return under IC 6-5.5.
(4) A utility receipts tax return under IC 6-2.3 (before its repeal).
(5) A claim for refund of any tax described in subdivisions (1) through (4).