For any true stickler, you see, the sight of the plural word “Book’s” with an apostrophe in it will trigger a ghastly private emotional process similar to the stages of bereavement, though greatly accelerated. First there is shock. Within seconds the shock gives way to disbelief, disbelief to pain, and pain to anger. Finally (and this is where the analogy breaks down), anger gives way to a righteous urge to perpetrate an act of criminal damage with the aid of a permanent marker.
-Lynne Truss, Eats, Shoots & Leaves, 2003