Generalisations of the Laplace-Runge-Lenz vector
  The characteristic feature of the Kepler Problem is the existence of the so-called Laplace--Runge--Lenz vector which enables a very simple discussion of the properties of the orbit for the problem. It is found that there are many classes of problems, some closely related to the Kepler Problem and others somewhat remote, which share the possession of a conserved vector which plays a significant r\^ole in the analysis of these problems. 
P.G.L. Leach and G.P. Flessas