Ill. Admin. Code tit. 44, § 30.65
b) Proof of citizenship or permanent residency must be confirmed by a birth certificate, naturalization papers, permanent resident status documents, passports or other documents.
(Recodified from Section 10.65 of 44 Ill. Adm. Code 10 (Central Management Services) pursuant to P.A. 101-657, at 47 Ill. Reg. 279)