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.
Mallards are the most widely distributed waterfowl species in the Northern Hemisphere. They can be found from the Arctic to the subtropics in Asia, Europe, and North America. The mallard is the most common migrating waterfowl species found in South Carolina. Many varieties of domestic ducks have a mallard ancestry.