This edition is based on the manuscripts kept in Berlin at the Staatsbibliothek - Preußischer Kulturbesitz (KHM 1323-1508) and on some copies kept in various European libraries. The Berlin manuscripts are the copies that Frederick the Great had made for personal use in his residences. Of each Solo there are two copies "pour Potsdam" and two "pour le nouveau Palais" whereas those that were supposedly made also "pour Sans Souci" are missing, as attested by Quantz Solos...