Book excerpt: On the top of a cliff overlooking the sea was an oak tree that was 365 years old. It was an unimaginable age for the mayflies, tiny creatures who lived only one day. The oak only slept during the winter. The rest of the year, he remained alert. That year, like every year, he began to lose his leaves in autumn. He knew that he was about to go to sleep for the last time! Hans Christian Andersen (1805-1875) was a Danish author, poet and artist. Celebrated for children’s literature, his most cherished fairy tales include "The Emperor's New Clothes", "The Little Mermaid", "The Nightingale", "The Steadfast Tin Soldier", "The Snow Queen", "The Ugly Duckling" and "The Little Match Girl". His books have been translated into every living language, and today there is no child or adult that has not met Andersen's whimsical characters. His fairy tales have been adapted to stage and screen countless times, most notably by Disney with the animated films "The Little Mermaid" in 1989 and "Frozen", which is loosely based on "The Snow Queen", in 2013. Thanks to Andersen's contribution to children's literature, his birth date, April 2, is celebrated as International Children's Book Day.