Add the date of publication

Error²Federal courts, Illinois courts21st and 22nd editions

A United Nations masthead document closes on the date it was published, in a parenthetical behind the document symbol; a yearbook is dated by its volume year instead.¹

1. 1R. 21.7.4 Masthead Documents. Tables: R. 21.7.4(c) United Nations document symbol.
2. 2An error: the rule in note 1 allows one form, and this is not it.