A Computer Program for the Nonnumerical Testing and Reduction of Sets of Algebraic Partial Differential Equations.

Carl H. Brans A Computer Program for the Nonnumerical Testing and Reduction of Sets of Algebraic Partial Differential Equations. 45-62 1967 14 J. ACM 1 http://doi.acm.org/10.1145/321371.321375 db/journals/jacm/jacm14.html#Brans67