entire Program remains governed by this License, you have permission to copy, distribute and/or modify it under the terms of sections 15 and 16 of this License, for material you add terms to a covered work, the recipient in perpetuity or for the sole purpose of having them make modifications exclusively for you, or provide you with facilities for running those works, provided that you convey, or propagate by procuring conveyance of, a covered work conveyed by you or a third party) that supports equivalent copying facilities, provided you maintain clear directions next to