Use the correct abbreviation

Warning²Federal courts, Illinois courts21st and 22nd editions

A shortened word in an institutional editor's name takes the table's own punctuation, not a private contraction of it.¹

1. 1R. 15.2(b) Institutional editors. Tables: T6 Case Names and Institutional Authors in Citations; T10 Geographical Terms; R. 15.1(e) Abbreviations; R. 15.1(d) Abbreviations.
2. 2A warning: the form is usually wrong under the rule in note 1, and context can justify it.