A Differentiation Index for Partial Differential-Algebraic Equations. - Wade S. Martinson; Paul I. Barton (SIAM J. Sci. Comput., 2000)

Differential-Algebraic Equations of Index 1 May Have an Arbitrarily High Structural Index. - Gunther Reissig; Wade S. Martinson; Paul I. Barton (SIAM J. Sci. Comput., 2000)

Index and Characteristic Analysis of Linear PDAE Systems. - Wade S. Martinson; Paul I. Barton (SIAM J. Sci. Comput., 2003)