Berlin, Stockholm, Paris, Beijer, 1886. 4to. With the original wrappers in ""Acta Mathematica, 9:2. Band]. No backstrip. Fine and clean. Pp. 131-36. [Entire issue: Pp. 105-184].
First printing of Zeller's paper important paper in which Zeller's congruence is presented It is an algorithm to calculate the day of the week for any Julian or Gregorian calendar date.