Martijn Theodoor Houtsma

Martijn Theodoor Houtsma (Irnsum, Friesland, 15 January 1851 – Utrecht, 9 February 1943), often referred to as M. Th. Houtsma, was a Dutch orientalist. He was a fellow of the Royal Netherlands Academy of Arts and Sciences, and a leading expert on the history of the Seljuks. He remains best known for his work as editor of the first edition (1913–38) of the standard encyclopedic reference work on Islam, the Encyclopaedia of Islam.