Add the full citation

Error²Federal courts, Illinois courts21st and 22nd editions

“Id.” repeats the authority cited immediately before it, so the first reference to an authority is given in full instead.¹

1. 1R. 4.1 “Id.”; B4 Short Citation Forms; B15.2 Short Form Citation; B16.2 Short Form Citation; B17.2 Short Form Citation; B18.2 Short Form Citation. Tables: R. 16.9(a) Id; R. 23.12 Short Citation Forms.
2. 2An error: the rule in note 1 allows one form, and this is not it.