Aers, Lesley. 'The Treatment of Time in Four Children's Books." Children's Literature in Education 2 (1970): 6981. The novel is discussed in the context of other children's books concerned with the theme of time.

Cameron, Eleanor. The Green and Burning Tree: On the Writing and Enjoyment of Children's Books. Boston: Little, Brown, 1969. Based on a lecture, a chapter of this study deals with time fantasies written for young adults.