Report of the IAU/IAG/COSPAR Working Group on Cartographic Coordinates and Rotational Elements of the Planets and Satellites - 1991

Revised values are presented for the directions of the north poles of rotation, the prime meridians, and for the sizes and shapes of the planets and satellites. Also presented are definitions of rotational elements and the cartographic coordinate systems. These revised values and definitions are the results of a report provided every three years by an international working group with members from IAU, IAG, and COSPAR.