Question: Who was the author of both The Snowman and The Fir-Tree?

full_context: Document 1: The Little Match Girl: "The Little Match Girl" (Danish: "Den Lille Pige med Svovlstikkerne" , meaning "The little girl with the matchsticks") is a short story by Danish poet and author Hans Christian Andersen. The story, about a dying child's dreams and hope, was first published in 1845. It has been adapted to various media, including an animated short film, a television musical, and an animated virtual reality story called "Allumette".
Document 2: Allumette: A Fable: Allumette; A Fable, with Due Respect to Hans Christian Andersen, the Grimm Brothers, and the Honorable Ambrose Bierce, by Tomi Ungerer, was originally published in 1974. It is a "reimagining" of "The Little Match Girl" by Hans Christian Andersen. The book's extended title references Andersen, for "The Little Match Girl", as well as fairy tale authors the Brothers Grimm, and satirist Ambrose Bierce. The book was initially published in 1974, and carried in the United States by Parents' Magazine Press and Scholastic, both bargain retailers. It was also briefly reprinted in 1986, but has since gone out of print again.
Document 3: The Snowman (fairy tale): "The Snowman" is a literary fairy tale by Hans Christian Andersen about a snowman who falls in love with a stove. It was published by C.A. Reitzel in Copenhagen as "Sneemanden" on 2 March 1861. Andersen biographer Jackie Wullschlager describes the tale as a lyrical and poignant complement to Andersen's "The Fir-Tree" of December 1844.
Document 4: Trees (poem): "Trees" is a lyric poem by American poet Joyce Kilmer. Written in February 1913, it was first published in "Poetry: A Magazine of Verse" that August and included in Kilmer's 1914 collection "Trees and Other Poems". The poem, in twelve lines of rhyming couplets of iambic tetrameter verse, describes what Kilmer perceives as the inability of art created by humankind to replicate the beauty achieved by nature.
Document 5: The Tree (book): The Tree is an autobiographical book by John Fowles. In it, Fowles discusses the essence of nature and its relation to the creative arts, especially writing.
Document 6: Origin of the Snow White tale: "Snow White" is a German fairy tale known across much of Europe and is today one of the most famous fairy tales worldwide. The Brothers Grimm published it in 1812 in the first edition of their collection "Grimms' Fairy Tales". It was titled in German: "Sneewittchen" (in modern orthography "Schneewittchen") and numbered as Tale 53. The Grimms completed their final revision of the story in 1854. It has generally been regarded as purely a tale of fiction. However, recent research suggests that the story may have been inspired from a real story.
Document 7: Little Claus and Big Claus: Little Claus and Big Claus (Danish title: Lille Claus og store Claus) is a tale by Hans Christian Andersen, published in Danish in 1835 in the first instalment of his booklet "Fairy Tales Told for Children. First Collection." (Danish title: "Eventyr fortalte for børn. Første Samling.").
Document 8: The Princess and the Pea: "The Princess and the Pea" (Danish: ""Prinsessen paa Ærten"" ; literal translation: "The Princess on the Pea") is a literary fairy tale by Hans Christian Andersen about a young woman whose royal identity is established by a test of her physical sensitivity. The tale was first published with three others by Andersen in an inexpensive booklet on 8 May 1835 in Copenhagen by C. A. Reitzel.
Document 9: The Fisherman and His Wife: "The Fisherman and His Wife" is a German fairy tale collected by the Brothers Grimm, tale no. 19. It is Aarne–Thompson type 555, the fisherman and his wife. Its theme was used in "The Tale of the Fisherman and the Fish", an 1833 poem by Aleksandr Pushkin. Virginia Woolf has her character Mrs. Ramsey in "To the Lighthouse" read a version of the story to her son, James. Günter Grass's 1977 novel, "The Flounder," is loosely based on the fairy tale, as are Emanuele Luzzati's version, "Punch and the Magic Fish," and Ursula LeGuin's novel "The Lathe of Heaven".
Document 10: Anne Frank tree: The Anne Frank tree (Dutch: Anne Frankboom or, incorrectly, "Anne Frank boom") was a horse-chestnut tree ("Aesculus hippocastanum") in the city center of Amsterdam that was featured in Anne Frank's "The Diary of a Young Girl". Anne Frank described the tree from The Annexe, the building where she and her family were hiding from the Nazis during World War II.
Document 11: The Nightingale (fairy tale): "The Nightingale" (Danish: "Nattergalen") is a literary fairy tale written by Danish author Hans Christian Andersen about an emperor who prefers the tinkling of a bejeweled mechanical bird to the song of a real nightingale. When the Emperor is near death, the nightingale's song restores his health. Well received upon its publication in Copenhagen in 1843 in "New Fairy Tales", the tale is believed to have been inspired by the author's unrequited love for opera singer Jenny Lind, the "Swedish nightingale". The story has been adapted to opera, ballet, musical play, television drama and animated film.
Document 12: Raymond Briggs: Raymond Redvers Briggs, CBE (born 18 January 1934) is an English illustrator, cartoonist, graphic novelist and author who has achieved critical and popular success among adults and children. He is best known in Britain for his story "The Snowman", a book without words whose cartoon adaptation is televised and whose musical adaptation is staged every Christmas.
Document 13: New Fairy Tales (1844): New Fairy Tales (Danish: "Nye Eventyr" ) is a collection of four fairy tales written by Hans Christian Andersen and published by C. A. Reitzel in Copenhagen, Denmark on 10 November 1843. As was customary at the time however, the title page is dated 1844. The tales are completely Andersen's invention, owe no debt to folk or fairy lore, and are the most autobiographical of his several fairy tale collections. The collection was received enthusiastically by the Danish critics and public and became Andersen's break-through in the fairy tale genre. "The Nightingale" and "The Ugly Duckling" have been adapted to various forms of drama.
Document 14: The Snowman: The Snowman is a children's picture book without words by English author Raymond Briggs, first published in 1978 by Hamish Hamilton in the United Kingdom, and published by Random House in the United States in November of the same year. In the UK, it was the runner up for the Kate Greenaway Medal from the Library Association, recognising the year's best children's book illustration by a British writer.
Document 15: The Fir-Tree: "The Fir-Tree" (Danish: "Grantræet") is a literary fairy tale by the Danish poet and author Hans Christian Andersen (1805–1875). The tale is about a fir tree so anxious to grow up, so anxious for greater things, that he cannot appreciate living in the moment. The tale was first published 21 December 1844 with "The Snow Queen", in Copenhagen, Denmark, by C.A. Reitzel. One scholar (Andersen biographer Jackie Wullschlager) indicates that "The Fir-Tree" was the first of Andersen's fairy tales to express a deep pessimism.
ground_truth: Hans Christian Andersen