A rather sneaky one from In the Shadows of Paris (Le Léopard des Batignolles) by Claude Izner:
Kenji, clean-shaven and smelling faintly of lavender, walked past the Théâtre Français. He liked to cut through the gardens of the Palais-Royal where he communed with the departed souls of Restif de la Bretonne, André Chénier, Musset, Stendhal and Cagliostro. Could any of them tell him whether the mysterious manuscript at the Bibliothèque National was his? Lucien de Rubempre whispered to him to stop chasing after illusions and enjoy the moment.
I especially enjoyed the above since it mentioned a character rather than the author’s name. A more ordinarily found one is this one from later in the book:
‘Have you forgotten? You’re supposed to give the Balzacs and the Diderots a polish and arrange them in the window.