(b) Other assessment powers.--If the mode or time for the assessment of any tax under this article (including interest, additions to tax and assessable penalties) is not otherwise provided for, the tax commission may establish the same by regulations.
(c) Estimated income tax.--No unpaid amount of estimated tax shall be assessed.
(d) Supplemental assessment.--The tax commission may, at any time within the period prescribed for assessment, make a supplemental assessment, subject to the provisions of section six hundred eighty-one where applicable, whenever it is ascertained that any assessment is imperfect or incomplete in any material respect.
(e) Cross reference.--For assessment in case of jeopardy, see section six hundred ninety-four.