Madeleine L'Engle was an American writer best known for her young adult fiction, particularly the Newbery Medal-winning A Wrinkle in Time and its sequels A Wind in the Door, A Swiftly Tilting Planet, and Many Waters. Her works reflect her strong interest in modern science: tesseracts, for example, are featured prominently in A Wrinkle in Time, mitochondrial DNA in A Wind in the Door, organ regeneration in The Arm of the Starfish, and so forth.