Ignore all bills and invoices included in interlibrary loan materials.The Penn Libraries does not charge our patrons for scans. Acquisition and delivery of materials through Interlibrary Loan and from High Density storage is a service of the Penn Library, provided free of charge to eligible Penn faculty, students, and staff. However, some libraries charge each other for these services. The Penn Library absorbs the charges associated with acquiring material needed for your study and research.