Knock-knocks are a perennial favorite with youngsters, and here are hundreds to keep them giggling. This new collection of uproarious knock-knocks will take kids (and their unwitting victims ) from A ( Knock-Knock . Who's there? Ammonia. Ammonia who? Ammonia little kid, so I can't reach the doorbell ) to Z ( Knock-Knock. Who's there? Zoe. Zoe who? Zoe doesn't recognize my voice now? ). With fantastic drawings that add to the fun, this pocket-sized...