Van den Bos , W.H. "Robert Grant Aitken. " National Academy of Sciences Biographical Memoirs 32 ( 1 958) : 1-30.
Alfonsine Tables The most widely used astronomical tables of the Middle Ages , c irculated under the name of Alfonso X, el sabio, King of Castille and Leon ( 1 2 5 2-1 284) . Their exact relationship co an earl ier sec of astronomical tables i n Cascillian, now lost, which were based upon original observations commissioned by the king , i s uncertain . The Lati n Alfons ine Tables first appeared in Paris around 1 3 20 , accompanied by a number of different can ons, or instructions, for their use written by such astronomers as John of Saxony.