Bip39 copyright https://franciscougju442.bravesites.com/entries/general/Produce-Bitcoin-Addresses-from-Seed-Every-Little-Thing-You-Required-to-Know The last move of BIP-39 is building the actual binary seed which can be then applied like a master important in BIP-32 deterministic wallet or using other procedures. For words that have only three letters, there is absolutely no 4th lette... https://www.sbnation.com/users/typhanhmdy