Written by Sally Grindley (1953) and illustrated by Anthony Browne (1946), this childrens picture book tells an excellent bedtime story and has been very popular since 1985. Who is knocking the door? Is it Gorilla, Witch, or Dragon?Written by Sally Grindley (1953) and illustrated by Anthony Browne (1946), this childrens picture book tells an excellent bedtime story and has been very popular since 1985. Who is knocking the door? Is it Gorilla, Witch, or Dragon?