Elling Holst
Elling Bolt Holst (19 July 18492 September 1915) was a Norwegian mathematician, biographer and children's writer. Early and personal life. Holst was born in Drammen, Norway. He was a son of bookseller Adolph Theodor Holst and Amalie Fredrikke Bergh. He was a grandson of merchant and politician, member of the Storting, Elling Mathias Holst (1785-1852). Holst enrolled as a student at the University of Christiania (now University of Oslo), his doctoral advisor was Sophus Lie, and he graduated as cand.real. in 1874. He continued his studies in Germany, where Felix Klein was among his teachers. He  was appointed teacher at Aars og Voss skole in Christiania (now Oslo). His thesis "Et par syntetiske Methoder, især til Brug ved Studiet af metriske Egenskaber" was finished in 1882. Career. Holst lectured in mathematics at the University of Oslo from 1894. Among his other mathematical works are his contribution from 1878, "Om Poncelets betydning for geometrien", and several course books. He wrote biographies of several mathematicians, including Cato Maximilian Guldberg, Carl Anton Bjerknes, Sophus Lie and Niels Henrik Abel. Holst is particularly known for his children's books "Norsk Billedbog for Børn", three collections from 1888, 1890 and 1903  (with illustrations by Eivind Nielsen). The first of these books has been called Norway's first national picture book (although a picture abc had been published previously, in 1876). Among his other children's books are "Julegodter for Børn" from 1892, and "A.B.C. for Skole og Hjem" from 1893 (together with Anna Rogstad). He published the picture book "Fra Sæteren" in 1899, with illustrations by Lisbeth Bergh. Personal life. He was married twice, first to Inger Skavlan (1852–99), and was a brother-in-law of Olaf Skavlan, Sigvald Skavlan, Aage Skavlan and Harald Skavlan. After her death, he married Marie  Michelet (1872–1960), sister of Simon Michelet, in 1900. He was decorated Knight, First Class of the Order of St. Olav in 1902.