When authors refer to other great works, people, and events, it’s usually not accidental. Put on your super-sleuth hat and figure out why.
Literature, Philosophy, and Mythology
Albert Camus: The Stranger (1.8.25)
Lucretius (1.5.6)
Historical Figures
Nostradamus (4.4.5)
St. Odilia (4.4.5)
Bishop Belzunce (4.4.16)
Pop Culture
Louis Armstrong (maybe): St. James Infirmary Blues (2.9.139, 2.9.229)
Christoph Willibald Ritter von Gluck: Orfeo ed Euridice (4.1.22)