CFR›Title 1›Chapter I›Part 21›Subpart B ContainsSections 21.40–21.42; Subject groups Form–PlacementCorpusDaily eCFRDisplayed edition2026-04-15Last updated2026-04-15 Subpart B—Citations of Authority Contents 21.40 § 21.40 General requirements: Authority citations. 21.41 § 21.41 Agency responsibility. 21.42 § 21.42 Exceptions. Form Form Sections 21.51–21.53 Placement Placement Sections 21.43–21.45 Previous A Subpart A—General