Violin Concerto No. 7 (Mozart) to the insertion of new works bearing the numbers K. 271b to K. 271H in the catalogue. He believed that the work was based on a rough sketch of a violin concerto by Mozart from 1777, but states that the original form of the work cannot easily be reconstructed. The uncharacteristic number of passages for the solo violin in the high register, in "pizzicato" (in the second movement), and in double stops in tenths were considered by Einstein to be 19th-century additions. Friedrich Blume, on the other hand, was firmly in favour of the work's authenticity, stating that "not one
Catalogues of Beethoven compositions and Hans Halm published a catalogue of Beethoven's works, in which they assigned numbers to 205 "Werke ohne Opuszahl" (meaning "works without opus number" in German) to "some" of Beethoven's unpublished works. These numbers given these works are generally preceded by "WoO". The Kinsky–Halm catalogue also lists 18 works in an appendix as being either doubtfully attributed, or simply spurious. Some of those listed as doubtful have since been shown to be authored by Beethoven. These numbers are generally preceded by "Anh.", short for German "Anhang", meaning "appendix". The Swiss composer and musicologist Willy Hess also researched and published a