Section 861.—Income From Sources Within the United States

26 CFR 1.861-8T: Computation of taxable income from sources within the United States and from other sources and activities (temporary). 26 CFR 1.861–9T: Allocation and apportionment of interest expense (temporary).

May a taxpayer that uses the fair market value method of valuing its assets for expense apportionment purposes obtain, by following certain specific procedures, automatic consent to switch to the alternative tax book value method within a certain limited time period. See Rev. Proc. 2005-28, page 1093.