How do you create a children's classic?
Picture book creator Oliver Jeffers and artist Sam Winston tell BBC News how they combined their skills to create a unique children's book.
They have created A Child Of Books which uses written words as part of the illustrations. The aim was to create something that celebrated literature with a modern twist.
Oliver and Sam are also setting this year's World Book Day Award (WoBoD) challenge.
Jeffers and Winston spoke to BBC News.
Video journalist Sophie van Brugen