by L. Frank Baum
The third of the Oz books (and I suspect the one where L. Frank Baum finally realized he was doomed to write these for life). Dorothy returns to Oz, we meet Tik-Tok the mechanical man and the rotten Nome King (who, all in all, is a pretty ineffective villain) as well as the hen Billina who turns out to be the heroine. Kids loved it.
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