Where relevant, the publication date listed in a Witness overview is accompanied by an indication in round brackets of its provenance – i.e. a particular register (e.g. of the Bibliothèque nationale de France) or reference source (see Bibliography for details). Where it has been impossible to include a copy of the first impression in the CFEO resource because no such score has been located, the date of the CFEO exemplar is given with an explanatory note regarding the first impression’s unavailability.

It should be noted that innumerable problems surround the dating of Chopin’s first editions; the Annotated Catalogue of Chopin’s First Editions explores these fully.