Schubert (1949) showed that every knot can be uniquely decomposed (up to the order in which the decomposition is performed) as a knot sum of a class of knots known as prime knots, which cannot themselves be further decomposed (Livingston 1993, p. 5; Adams 1994, pp.
The Moors were Muslim inhabitants of the Maghreb, the Iberian Peninsula, Sicily, and Malta during the Middle Ages.
A Moor in Spain, portrayed in a Cantiga (1200s AD) One of the oldest images of the crowned Freising Moor c. 1316 AD There were also several accounts of Moors in northern and central Europe, including that of the so-called Freising Moor..