This book's title:
http://imslp.org/wiki/Musikerelend_(Kre ... MSLP339869
translates as "Reflections on bleak and degrading conditions in the music profession". Sibley classified it as vocational guidance . . .
Not sure we should follow suit, so -- music history? Any other suggestions?
[edit] On a similar subject, something else was uploaded from Sibley http://imslp.org/wiki/Wer_ist_musikalis ... MSLP339877 that deals with the psychology of music. Suggestions for that?