Is it farther or further?
(RFP) The publication by a prospective software purchaser of details of the required system in order to attract offers by software developers to supply it. Software development under contract starts with the selection of the software developer by the customer. A request for proposal (also called in Britain an "invitation to tender") is the beginning of the selection process.
[Bennatan, E.M., "Software Project Management", 2nd edition, McGraw-Hill International, 1992].