50 CFR §91.16

1. (a)Each contestant may submit only one entry. Each entry must be accompanied by a non-refundable entrance fee and a completed and signed Reproduction Rights Agreement and a completed and signed Display and Participation Agreement. The bottom portion of the Reproduction Rights Agreement must be attached to the back of the entry.
2. (b)Each entry should be appropriately wrapped to protect the artwork and then either hand-delivered or sent by registered mail, certified mail, express mail, or overnight delivery service to: Federal Duck Stamp Contest, U.S. Fish and Wildlife Service, MS: MB, 5275 Leesburg Pike, Falls Church, VA 22041.