Encyclopaedia of Mathematics: vol 7: Orb-Ray
Hazewinkel, M.
Encyclopaedia of Mathematics: vol 7: Orb-Ray M. Hazewinkel - Dordrecht, Boston, London Kluwer Academic Publishers -1988
Encyclopaedia of Mathematics: vol 7: Orb-Ray M. Hazewinkel - Dordrecht, Boston, London Kluwer Academic Publishers -1988