(f) Any other documentation that proves an element of the taxpayer's resident credit.
(3) For the joint filing credit allowed under division (E) of section 5747.05 of the Revised Code:
(a) Federal wage and income statements for both spouses;
(b) The taxpayers' federal return, with accompanying schedules (including schedules C, E, and F), as filed with internal revenue service;
(c) Any other documentation that proves an element of the taxpayer's joint filing credit.
(B) The documentation listed in paragraphs (A)(1) and (A)(2) of this rule should be used by an individual who claims both the resident credit and nonresident credit during one taxable year.
(C) When claiming a credit under section 5747.05 of the Revised Code, the taxpayer will, when feasible, provide documentation relevant to the taxable year at issue when filing the taxpayer's Ohio income tax return. If the documentation is not provided with the return, the taxpayer will provide the information upon request of the commissioner.