A Wizard of Earthsea by Ursula K. Le Guin
No one really liked Duny. The boy was wild, proud, and full of temper-- well-suited to the company of the goats he herded. Then came the day when he overheard his aunt chanting a spell to call her goat down from the roof of her house. He remembered the rhyme and later spoke it to his own herd:
"Noth hierth malk man hiolk han merth han!"