...If previously made) at any time before the expiration of the period prescribed by section 6511 (a) (or section 6511(c) if the period is extended by agreement)...credit or refund of the tax Imposed by chapter 1 for such taxable year. Such period for such taxable year is determined without regard to the special period...

...at any time before the expiration of the period prescribed by section 651 Ha) (or section 651 lie) If the period is extended by agreement) for making...credit or refund of the tax imposed by chapter 1 for such taxable year. Such period for such taxable year is determined without regard to the special period...

...under section 617(a) may be made at any time before the expiration of the period prescribed for filing a claim for credit or refund of the tax Imposed by chapter 1 for the first taxable year for which the taxpayer desires to deduct exploration expenditures under section 617(a). (3) Revocation of election...

...under section 617(a) may be made at any time before the expiration of the period prescribed for filing a claim for credit or refund of the tax imposed by chapter 1 for the first taxable year for which the taxpayer desires to deduct exploration expenditures under section 617. (3) Timely mailing treated...

...time before the expiration of the period (including extensions thereof) prescribed in section 6511 for making a claim for credit or refund of the tax imposed by chapter 1 for such taxable year. However, such period is not extended by the right to make or change such election....

...Elections under section 1078 of the Act shall be made by the later of the expiration of the period for making a claim for credit or refund of the tax imposed by Chapter 1 of the Code for the taxable year in which the reinvestment of the payment occurred, or July 18, 1985....

...election under subsection (a) may be made or revoked at any time before the expiration of the period for making a claim for credit or refund of the tax imposed by this chapter for the taxable year in which the sale or exchange occurred, and shall be made or revoked...

...election under subsection (a) may be made or revoked at any time before the expiration of the period for making a claim for credit or refund of the tax imposed by this chapter for the taxable year in which the sale or exchange occurred, and shall be made or revoked...

...section 6511(a), or by section 651 1(c) if the period for assessment is extended by agreement, for filing a claim for credit or refund of the tax imposed by chapter 1 of the Code for such taxable year. This election may be made without the consent of the Commissioner....

...time before the expiration of the period (including extensions thereof) prescribed in section 6511 for making a claim for credit or refund of the tax imposed by 1.1304-3 chapter 1 of the Code for such taxable year. (b) Subsequent qualification. A taxpayer who...