Quartic Equations and Algorithms for Riemann Tensor Classification.

Jan E. Åman R. A. d'Inverno G. C. Joly Malcolm A. H. MacCallum Quartic Equations and Algorithms for Riemann Tensor Classification. 47-58 1984 conf/eurosam/1984 EUROSAM db/conf/eurosam/eurosam1984.html#AmandJM84 http://dx.doi.org/10.1007/BFb0032829