Question: What pair of authors used themes and characters from a fairy tale published in 1812?
Context: "Snow White" is a 19th-century German fairy tale which is today known widely across the Western world.  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 name "Sneewittchen" was Low German and in the first version it was translated with "Schneeweißchen".  The Grimms completed their final revision of the story in 1854. "Rapunzel" ( ; ] ) is a German fairy tale in the collection assembled by the Brothers Grimm, and first published in 1812 as part of "Children's and Household Tales".  The Grimm Brothers' story is an adaptation of the fairy tale "Rapunzel" by Friedrich Schulz published in 1790.  The Schulz version is based on "Persinette" by Charlotte-Rose de Caumont de La Force originally published in 1698 which in turn was influenced by an even earlier Italian tale, "Petrosinella" by Giambattista Basile, published in 1634.  Its plot has been used and parodied in various media and its best known line ("Rapunzel, Rapunzel, let down your hair") is an idiom of popular culture.  In volume I of the 1812 annotations (Anhang), it is listed as coming from Friedrich Schulz Kleine Romane, Book 5, pp. 269–288, published in Leipzig 1790. Fairer-than-a-Fairy (French "Le Prince Arc-en-ciel", The Rainbow Prince) is a literary fairy tale published anonymously in the 1718 fairy tale collection "Nouveaux contes de fées".  It is attributed to the Chevalier de Mailly.  Andrew Lang included it in "The Yellow Fairy Book". The Squirrel Wife is the title of a children's fairy tale written by Philippa Pearce and first illustrated by Derek Collard.  This original fairy tale published by Longman Young in 1971 has subsequently been republished in Middlesex: New York City; Paris and Madrid.  Bill Geldart is responsible for illustrating publications made between 1983–1992 and Wayne Anderson most recently illustrated both New York and London publications in 2007.  The squirrel wife is also included within "The Faber book of Modern Fairy Tales". "The Heart of Princess Joan" is a 19th-century fairy tale published in 1880 as part of the collection "The Necklace of Princess Fiorimonde and other Stories".  This was the second of three published collections of fairy tales by popular children’s author, Mary De Morgan.  Illustrations for the stories were provided by Walter Crane. "The Professor of Practical Jokes" is a literary fairy tale published in 1898 by British suffragist and author Evelyn Sharp (1829–1955).  The story tells of a good yet boring king who is tricked into marrying one of his courtiers daughters, who brings excitement into his dull kingdom.  The story is one of many published in Sharp's collection, All The Way To Fairyland: Fairy Stories. La petite Toute-Belle ("Little Toute-Belle") is a Breton fairy tale published in 1900 by Paul Sébillot in "Contes des landes et des grèves". "Cap-o'-Rushes" is an English fairy tale published by Joseph Jacobs in "English Fairy Tales". "Sleeping Beauty" (French: "La Belle au bois dormant" "The Beauty Sleeping in the Wood") by Charles Perrault, or "Little Briar Rose" (German: "" ), is a classic fairy tale which involves a beautiful princess, a sleeping enchantment, and a handsome prince.  The version collected by the Brothers Grimm was an orally transmitted version of the originally literary tale published by Charles Perrault in "Histoires ou contes du temps passé" in 1697.  This in turn was based on "Sun, Moon, and Talia" by Italian poet Giambattista Basile (published posthumously in 1634), which was in turn based on one or more folk tales.  The earliest known version of the story is found in the narrative "Perceforest", composed between 1330 and 1344 and first printed in 1528. Grimmtastic Girls is a series of children's books written by Joan Holub and Suzanne Williams.  It uses themes and characters from fairy tales, including Cinderella, Little Red Riding Hood, Rapunzel, Snow White, Sleeping Beauty, and Goldilocks.  The series is set at Grimm Academy in the country of Grimmlandia.  The first book, "Cinderella Stays Late", was published in 2014.
Answer: Joan Holub and Suzanne Williams