Richard Wagner's Letters To His Dresden Friends, Theodor Uhlig, Wilhelm Fischer, And Ferdinand Heine (1890)
https://archive.org/details/cu31924017112628/page/n11/mode/2up
Beethoven (1905)
60 pages long. Divided into short chapters. Sheet music on pages 36–37, 44–47 & 51–54.
Bell's Miniature Series Of Musicians.https://archive.org/details/beethoven00sheduoft/page/n3/mode/2up
Beethoven's Pianoforte Sonatas: The Origin And Respective Values Of Various Readings (1918)
43 pages long. Sheet music included.https://babel.hathitrust.org/cgi/pt?id=njp.32101065674747&view=2up&seq=8