First References to Mahler in Fiction?

[David Boxwell]

[The elderly Baroness Geldern] pressed her narrow lips together and said ornamentally, "Perhaps it is retrograde on our part not to have learned to appreciate that ugly art is better than beautiful art. I cannot get it into my head," she confessed and smiled wanly, "that Gustav Mahler is supposed to be more worthwhile than my Mendelssohn-Bartholdly . . ."

Klaus Mann, "Der Fromme Tanz" ("The Pious Dance", 1925 [trans. Laurence Senelick])

Are there earlier allusions in creative writing to GM before 1925?