On the catalog entries

UPDATE: Each entry has been critically reviewed and rewritten with all available information (literature, archives, databases, own research) and reflects the state of knowledge as of 2020/2021. The catalog is continually expanded and updated as new information becomes available.
PICTURE TITLE: Each painting is uniquely identified for the catalog and the works database and follows the pattern of picture title (subject or person depicted) and year of creation. Picture titles follow the historically documented first picture title (usually by the artist himself as documented in the Künstlerhaus entry books or in the literature). Noble titles are therefore still given for pictures after 1918, although this has been illegal in Austria. Historical authenticity is given preference here over a largely dead legal regulation. This also applies to the -- from today's point of view absurd -- historical convention to call women by the names of their husbands (e.g. Mrs John Warner), i.e. to make them nameless. Here, too, the original historical picture title is retained for reasons of authenticity. Exceptions are made in cases where the original title of the picture (e.g. only "Portrait of a Lady") does not allow a clear identification. In these cases, new, unambiguous picture titles are assigned, whereby imaginative new titles by the auction houses are reduced to as simple and neutral a title as possible.
AUTHORS: Unnamed catalog entries were written by the catalog's editor (Arnulf Grübler). Designated contributions by the respective experts/authors are listed by name. Their contribution was made free of charge. The editor assumes ultimate responsibility for the accuracy of all entries, leaving artistic aspects and evaluations to the freedom of science and thus to the responsibility of the contributors.
ABBREVIATIONS AND TERMINI To make entries consistent with the limited space available in the online format, abbreviations are used for recurring entries. The most important of these are: EL 49 1905/06 #1416 = Künstlerhaus Einlaufbücher (entry books), volume number (49), year (1905/06), followed by entry number (#1416). APH, Werksverzeichnis JQA 1995, p. 60, cat.#29, fig.#17 = Alexandra Peyer-Helmstätt, Der Wiener Maler John Quincy Adams (Werksverzeichnis), thesis University of Vienna, September 1995, page (60), catalog number (#29), figure number (#17). Schaffer/Eisenburger 1986, Exhibition Catalog #5 = Nikolaus Schaffer (Author) and Sylvia Eisenburger (Editor), Viennese Society in Portrait - The Painter John Quincy Adams - Exhibition Catalog, Academy of Fine Arts, Vienna, July 9-August 10, 1986. Academy of Fine Arts Schillerplatz 3 1010 Vienna and Society of Friends of Fine Arts, Vienna (Publishers), catalog number (#5).
Subjective Evaluations: In the absence of written sources or literature, (subjective) confidence statements are assigned (in decreasing order of probability of truth):
Likely = (very) likely (supported by comparisons, press quotations, or oral statements of families and owners (but not substantiated by clear picture-related sources).
Probably (hypothesis supported by indirect evidence, such as image comparisons, suspected by the author of the catalog entry).
Possibly (alternative hypothesis, but evaluated by the author of the catalog entry as less probable than other evaluations such as likely or probably).