Question: Dorothy and the Wizard in Oz is the fourth book written by who?

Context paragraphs:
Wicked (musical): Wicked: The Untold Story of the Witches of Oz is a Broadway musical with music and lyrics by Stephen Schwartz and book by Winnie Holzman.  It is based on the 1995 Gregory Maguire novel "", an alternative telling of the 1939 film "The Wizard of Oz" and L. Frank Baum's classic 1900 story, "The Wonderful Wizard of Oz".  The musical is told from the perspective of the witches of the Land of Oz; its plot begins before and continues after Dorothy's arrival in Oz from Kansas, and it includes several references to the 1939 film and Baum's novel.  "Wicked" tells the story of two unlikely friends, Elphaba (the Wicked Witch of the West) and Galinda (whose name later changes to Glinda the Good Witch), who struggle through opposing personalities and viewpoints, rivalry over the same love-interest, reactions to the Wizard's corrupt government and, ultimately, Elphaba's public fall from grace.

Return to Oz: Return to Oz is a 1985 fantasy adventure film directed and written by Walter Murch, an editor and sound designer, co-written by Gill Dennis and produced by Paul Maslansky.  It stars Nicol Williamson as the Nome King, Jean Marsh as Princess Mombi, Piper Laurie as Aunt Em, Matt Clark as Uncle Henry and introduces Fairuza Balk as Dorothy Gale.  It is loosely based on L. Frank Baum's "Oz" novels, mainly "The Marvelous Land of Oz" (1904) and "Ozma of Oz" (1907), yet is set six months after the events of the first novel, "The Wonderful Wizard of Oz" (1900) took place.  Although it is not a sequel and unrelated to the 1939 Metro-Goldwyn-Mayer film, "The Wizard of Oz", it borrows a few elements of it such as the ruby slippers.

Aunt Em: Aunt Em is a fictional character from the Oz books.  She is the aunt of Dorothy Gale and wife of Uncle Henry, and lives together with them on a farm in Kansas.  In "The Wonderful Wizard of Oz", she is described as having been a "young, pretty wife" when she arrived at Uncle Henry's farm, but having been "grayed" by her life there, implying that she appears older than one might expect from her chronological age.  Baum tells us that when Dorothy first came to live with her, Em would "scream and press her hand upon her heart" when startled by Dorothy's laughter, and she appears emotionally distant to her at the beginning of the story.  However, after Dorothy is restored to her at the end of the book, we see her true nature: she cries out, "My darling child!"  and covers her with kisses.

List of Oz books: The Oz books form a book series that begins with "The Wonderful Wizard of Oz" (1900) and relate the fictional history of the Land of Oz.  Oz was created by author L. Frank Baum, who went on to write fourteen full-length Oz books.  All of the Baum written books are in the public domain in the United States.  Even while he was alive, Baum was styled as "the Royal Historian of Oz" to emphasize the concept that Oz is an actual place.  The illusion created was that characters such as Dorothy and Princess Ozma related their adventures in Oz to Baum themselves, by means of wireless telegraph.

Glinda of Oz: Glinda of Oz is the fourteenth Land of Oz book written by children's author L. Frank Baum, published on July 10, 1920.  It is the last book of the original Oz series, which was later continued by other authors.  Like most of the Oz books, the plot features a journey through some of the remoter regions of Oz; though in this case the pattern is doubled: Dorothy and Ozma travel to stop a war between the Flatheads and Skeezers; then Glinda and a cohort of Dorothy's friends set out to rescue them.  The book was dedicated to Baum's second son, Robert Stanton Baum.

The Magic of Oz: The Magic of Oz: A Faithful Record of the Remarkable Adventures of Dorothy and Trot and the Wizard of Oz, Together with the Cowardly Lion, the Hungry Tiger and Cap'n Bill, in Their Successful Search for a Magical and Beautiful Birthday Present for Princess Ozma of Oz is the thirteenth Land of Oz book written by L. Frank Baum.  Published on June 7, 1919, one month after the author's death, "The Magic of Oz" relates the unsuccessful attempt of the Munchkin boy Kiki Aru and former Nome King Ruggedo to conquer Oz.

The Lost Princess of Oz: The Lost Princess of Oz is the eleventh canonical Oz book written by L. Frank Baum.  Published on June 5, 1917, it begins with the disappearance of Princess Ozma, the ruler of Oz and covers Dorothy and the Wizard's efforts to find her.  The introduction to the book states that its inspiration was a letter a little girl had written to Baum: "I suppose if Ozma ever got hurt or losted, everybody would be sorry."

Dorothy and the Wizard in Oz: Dorothy and the Wizard in Oz is the fourth book set in the Land of Oz written by L. Frank Baum and illustrated by John R. Neill.  It was published on June 18, 1908 and reunites Dorothy with the humbug Wizard from "The Wonderful Wizard of Oz" (1900).  This is one of only two of the original fourteen Oz books (the other being "The Emerald City of Oz" (1910), to be illustrated with watercolor paintings.

Nathaniel D. Mann: Nathaniel D. Mann was an American composer best known for his work with L. Frank Baum.  He composed at least two songs with Baum, "Different Ways of Making Love" and "It Happens Ev'ry Day," and another with John Slavin, "She Didn't Really Mind the Thing at All," for "The Wizard of Oz" stage musical in 1902, and in 1908, composed the first original film score (27 cues) for "The Fairylogue and Radio-Plays", one of the earliest feature-length fiction films (and the earliest film adaptations of the novels "The Wonderful Wizard of Oz", "The Marvelous Land of Oz", "Ozma of Oz", "John Dough and the Cherub", and "Dorothy and the Wizard in Oz", presented by Baum himself), which debuted September 24, 1908.  With Baum, he also composed the musical "The King of Gee-Whiz" (dated February 23, 1905), which went through various titles such as "Montezuma" (November 1902), "King Jonah XIII" (September 1903), and "The Son of the Sun" (1905).  This was collaboration with and based on a novel by Emerson Hough, which was never completed and the extant scenario published in 1969.

List of published Oz apocrypha: This page is a supplement to List of Oz books featuring published books, often by small publishing houses.  Their canonicity is up to the individual reader, with some purists considering them apocryphal.  As the Baum Oz books are in the public domain, no clearance needs to be obtained to write and publish fiction about the Oz characters, professionally or otherwise, making the question of canonicity somewhat subjective.  Additionally, both of Jack Snow's Oz books are in the public domain in the United States, as are Ruth Plumly Thompson's "The Royal Book of Oz", "Kabumpo in Oz", "The Wishing Horse of Oz", "Captain Salt in Oz", "Handy Mandy in Oz", "The Silver Princess in Oz", and "Ozoplaning with the Wizard of Oz", making the distinctive elements in those books usable as public domain content.  The most dramatic changes in her books are in "The Lost King of Oz" and "The Giant Horse of Oz", both of which remain protected under U.S. copyright law, and has rendered some known manuscripts unpublishable.  The Oz books of John R. Neill, Rachel R. Cosgrove, and Eloise Jarvis McGraw and her daughter Lauren are all protected under U.S. copyright, making their characters and developments unusable by others without permission.

Supporting paragraphs: Nathaniel D. Mann Dorothy and the Wizard in Oz
Answer: L. Frank Baum