Sec. 25.6601-1 Interest on underpayment, nonpayment, or extensions of time for payment, of tax.
For regulations concerning interest on underpayment, nonpayment, or extensions of time for payment of tax, see section 301.6601-1 of this chapter (Regulations on Procedure and Administration).
[T.D. 6334, 23 FR 8904, Nov. 15, 1958]