But this week I can add a third one:
Added 2 August 2020:
I have now discovered a variant on the genre. I just bought a Penguin Modern Classics edition of Nabokov's Ada or Ardor. The spare pages at the end are used to advertise other books by Nabokov. This is how Penguin introduces its edition of Lolita:
"Humbert Humbert - scholar, aesthete and romantic - has fallen completely and utterly in love with Lolita Haze ......"