Add the comma before the paragraph

Error²Federal courts, Illinois courts21st and 22nd editions

A paragraph pincite follows a public-domain citation as “, ¶ 22” — comma, space, symbol, space, number.¹

1. 1Style Manual for the Supreme and Appellate Courts of Illinois pt. III(A)(3); R. 10.3.3 Public Domain Format; T1.3 States and the District of Columbia.
2. 2An error: the rule in note 1 allows one form, and this is not it.