Slowly going through North American classic children's books. There are references to them almost everywhere you look—but I never get them, because I grew up with H.C. Andersen, not Baum or Montgomery (Anne of Green Gables). In general, I'd much prefer to refer to a concept such as whether a system is still itself after all the parts have been replaced through the tinman in Oz, then call in Plutarch and the Ship of Theseus. Feels like shooting cannonballs at flies (and somewhat pretentious when a simpler example can do).