I'll nominate
Love in a cold climate by Nancy Mitford
"Groomed for the perfect marriage by her mother, fearsome Lady Montdore, Polly instead scandalizes society by declaring her love for her uncle ‘Boy’ Dougdale, the Lecherous Lecturer, and promptly eloping to France. But the consequences of this union no one could quite expect..."
I've found it at
Amazon,
BooksOnBoard and
Waterstones.