42 C.F.R. § 412.511
Reporting and recordkeeping requirements
A long-term care hospital participating in the prospective payment system under this subpart must meet the requirement of §§ 412.22(e)(3) and 412.22(h)(6) to report co-located status, if applicable, and the recordkeeping and cost reporting requirements of §§ 413.20 and 413.24 of this subchapter.