Three into Two Won't Go, Andrea Newman. Penguin, 1976.
Vintage paperback. Significant creasing to cover. No markings inside. Fair+ condition.
Andrea Newman was a British novelist and screenwriter.
"Steven and Frances are struggling to save their marriage: she wants a child and he wants sexual variety. Can Ella satisfy them both, or is she playing a dangerous game of her own? Divide three into two and there's always one over." (from Goodreads on Three into Two Won't Go).