From Tokyo Itoishigesato Jimusho (translated by Illuminati-Manga):

Born in 1931. Poet. His works, such as "Morning Relay", "2 Billion Years of Solitude", "Dolphin", "Listen Carefully", "To Live", have been collected in countless numbers of books. He is also the translator of Leo Lionni's "Swimmy", the "Peanuts" series, famous for Snoopy, and "The Rhymes of Mother Goose," and wrote the lyrics to the theme song of "Atom Boy" and "The Song of the Days of the Week."
He has been actively holding live performances where he recites his poems.

He won the American Book Award in 1989 for "Floating the River in Melancholy", translated by William I. Eliott and Kazuo Kawamura, and in 2008 he was nominated for the Hans Christian Andersen Award for his contributions to children's literature.