Question: Charles Wallace Murray is a major character in a fantasy/science fiction series of how many young adult novels written by Madeleine L'Engle?

full_context: Document 1: Eustace Scrubb: Eustace Clarence Scrubb is a fictional character in C. S. Lewis's Chronicles of Narnia. He appears in "The Voyage of the Dawn Treader", "The Silver Chair", and "The Last Battle". In "The Voyage of the Dawn Treader", he is accompanied by Edmund and Lucy Pevensie, his cousins. In "The Silver Chair" and "The Last Battle", he is accompanied by Jill Pole, a classmate from his school.
Document 2: Jody Lee: Jody A. Lee is a professional fantasy artist from San Francisco known best for her book cover illustrations. Authors she has worked with include Mercedes Lackey, Mickey Zucker Reichert, Lloyd Alexander, Madeleine L'Engle, and many others. She also painted role-playing games' covers such as "RuneQuest" (third edition, 1984) and "Pendragon" (first edition, 1985). She illustrated the 1991 and 1996 book covers for "A Wrinkle in Time", as published by Dell Yearling.
Document 3: Mr. Tumnus: Tumnus is a fictional character in C. S. Lewis' series "The Chronicles of Narnia". He is featured prominently in "The Lion, the Witch and the Wardrobe" and also appears in "The Horse and His Boy" and "The Last Battle". He is close friends with Lucy Pevensie and is the first creature she meets in Narnia, as well as the first Narnian to be introduced in the series. Lewis said that the first Narnia story, "The Lion, the Witch and the Wardrobe", all came to him from a single picture he had in his head of a faun carrying an umbrella and parcels through a snowy wood. In that way, Tumnus was the initial inspiration for the entire Narnia series.
Document 4: The Moon by Night: The Moon by Night (ISBN  ) is the title of a young adult novel by Madeleine L'Engle. Published in 1963, it is the second novel about Vicky Austin and her family, taking place between the events of "Meet the Austins" (1960) and "The Young Unicorns" (1968), and more or less concurrently with the O'Keefe family novel "The Arm of the Starfish". The book marks the first appearance of the character Zachary Gray, who dates first Vicky and then (in later books) Polly O'Keefe. Although Vicky will later appear in three novels that have fantasy and/or science fiction themes, there are no such elements in "The Moon By Night".
Document 5: The Giver Quartet: The Giver Quartet is a series of four young adult novels by Lois Lowry. The quartet consists of "The Giver" (1993), "Gathering Blue" (2000), "Messenger" (2004) and "Son" (2012). The first book won the 1994 Newbery Medal and has sold more than 10 million copies. The story takes place in the world of the Giver. Each book has a different protagonist, but is set in the same futuristic era.
Document 6: Calvin O'Keefe: Calvin O'Keefe is a major character in Madeleine L'Engle's "Time Quartet" series of books, and, as "Dr. Calvin O'Keefe", an important character in her O'Keefe series of young adult novels. In an interview released on the DVD of the TV adaptation of "A Wrinkle in Time", L'Engle describes Calvin as "the boy that we all, all us girls want to meet. Not all of us are lucky enough to meet a Calvin, but I was. And I married mine."
Document 7: Time Quintet: The Time Quintet is a fantasy/science fiction series of five young adult novels written by Madeleine L'Engle.
Document 8: Charles Wallace Murry: Charles Wallace Murry is a major character in Madeleine L'Engle's Time Quintet series of young adult science fiction novels. He is first introduced in L'Engle's "A Wrinkle in Time" as the youngest sibling of the protagonist, Meg Murry, and accompanying her on her adventures alongside Calvin O'Keefe.
Document 9: Lucy Pevensie: Lucy Pevensie is a fictional character in C. S. Lewis's "The Chronicles of Narnia" series. She is the youngest of the four Pevensie children, and the first to find the Wardrobe entrance to Narnia in "The Lion, the Witch and the Wardrobe". Of all the Pevensie children, Lucy is the closest to Aslan. Also, of all the humans who have visited Narnia, Lucy is perhaps the one that believes in Narnia the most. She is ultimately crowned Queen Lucy the Valiant, co-ruler of Narnia along with her two brothers and her sister. Lucy is the central character of the four siblings in the novels. Lucy is a principal character in three of the seven books ("The Lion, the Witch and the Wardrobe", "Prince Caspian", and "The Voyage of the Dawn Treader"), and a minor character in two others ("The Horse and His Boy" and "The Last Battle").
Document 10: Troubling a Star: Troubling a Star (ISBN  ) is the last full-length novel in the Austin family series by Madeleine L'Engle. The young adult suspense thriller, published in 1994, reunites L'Engle's most frequent protagonist, Vicky Austin, with Adam Eddington, both of whom become enmeshed in international intrigue as they travel separately to Antarctica. The story takes place several months after the end of "A Ring of Endless Light", the novel in which Vicky and Adam first met.
Document 11: Both Sides of Time: Both Sides of Time (1995) is a fiction book and the first of the Time Travelers Quartet series by Caroline B. Cooney. It was first published on July 1, 1995. The hardcover book has 224 pages and was published on October 9, 2001 by Delacorte Books for Young Readers. In Both Sides of Time, Caroline B. Cooney gives a realistic view of the struggles women had faced in the 19th century and how far they have come in the 20th century. The dialogue of this novel contains a mixture of the English language from the use of speech in the Victorian era to the terminologies and style of talk in modern English. The recommended age for this book is from ages 12 to 14.
Document 12: The Power of Five: The Power of Five (also known as The Gatekeepers in the US) is a series of five fantasy and suspense novels, written by English author Anthony Horowitz and published between 2005 and 2012. It is an updated re-imagining of Horowitz's "Pentagram" series, which the author had left unfinished in the 1980s. The series is published in the United Kingdom by Walker Books Ltd and in the United States by Scholastic Press. The novels deal heavily in the occult and examples of things such as human sacrifice and blood rituals are major plot elements, such as in the first book, where Matthew Freeman is hunted by a Cult who want to conduct a blood sacrifice on him to blast open a portal using a combination of nuclear physics and black magic, to unlock another dimension which is holding a group of ancient evil demons captive.
Document 13: Zachary Gray: Zachary Grey is a fictional character in the young adult novels of Madeleine L'Engle. He appears in four novels, and is mentioned in at least one more.
Document 14: Animorphs: Animorphs is a science fantasy series of young adult books written by Katherine Applegate and her husband Michael Grant, writing together under the name K. A. Applegate, and published by Scholastic. It is told in first person, with all six main characters taking turns narrating the books through their own perspectives. Horror, war, dehumanization, sanity, morality, innocence, leadership, freedom and growing up are the core themes of the series.
Document 15: A Wrinkle in Time (2018 film): A Wrinkle in Time is an upcoming American science-fiction fantasy adventure film directed by Ava DuVernay and written by Jennifer Lee. It is based on the 1963 novel of the same name by Madeleine L'Engle. The film stars Oprah Winfrey, Reese Witherspoon, Mindy Kaling, Storm Reid, Zach Galifianakis and Chris Pine. Principal photography on the film began on November 2, 2016, in Los Angeles, California.
ground_truth: five