Ruth Krauss (1901-1993), a member of the experimental Writer's Laboratory at the Bank Street School in New York City in the 1940s, imaginatively used humor and invented words to create some of the very first books for children that highlighted a child's inner life. She collaborated with some of the greatest illustrators in children's literature, including Maurice Sendak and her husband, Crockett Johnson.
Marc Simont (1915-2013) illustrated nearly a hundred books. He won a Caldecott Honor in 1950 for illustrating Ruth Krauss's
The Happy Day, and in 1957 he was awarded the Caldecott Medal for his pictures in
A Tree Is Nice by Janice May Udry. He is the illustrator for The New York Review Children's Collection books
The Wonderful O and
The 13 Clocks.