Like several of Christie's novels (e.g., Hickory Dickory Dock, One, Two, Buckle My Shoe) the title and substantial parts of the plot reference a nursery rhyme, in this case Sing a Song of Sixpence.
Converse (shoe company) | Red Shoe Diaries | Bally Shoe | Webb School (Bell Buckle, Tennessee) | Richard Reid (shoe bomber) | shoe | Paul Buckle | Niels Shoe Meulman | Henry Thomas Buckle | Buckle | Bell Buckle, Tennessee | Athletic shoe | Buckle (clothing retailer) | buckle | White shoe firm | West Coast Shoe Company | Werner Herzog Eats His Shoe | There was an Old Woman Who Lived in a Shoe | Spectator shoe | Shoe studs | Shoe polish | shoe polish | Shoe fetishism | Shoe-banging incident | Richard Buckle | Pointe shoe | Plimsoll shoe | Platform shoe | Pino "Little Shoe" Greco | Oxford shoe |