A notice is a public pronouncement that may contain guidance that involves substantive interpretations of the Internal Revenue Code or other provisions of the law. (Understanding IRS Guidance - A Brief Primer).
Notices appear in the Internal Revenue Bulletin and are included in the bound Cumulative Bulletin. Notices are identified by a two digit number representing the year and a sequence number. For example, Notice 95-67 is cited as Notice 95-67, 1995-2 C.B. 343. (IRS Manual 4.10.7.2.4.1 ).