John of London
John of London (fl. c. 1260), mathematician, was praised by Roger Bacon as one of two "perfect" mathematicians, together with Pierre de Maricourt, and superior to two good mathematicians, Campanus of Novara and Master Nicolas. He must have been known to Bacon in Paris in the 1260s.
He may be the John Bandoun also cited by Roger Bacon, and the Paris master, John of London who was learned in astronomy, the designer of a form of astrolabe and author of an influential table of stellar coordinates.