Abstract. In seeking suitable Runge-Kutta methods for differential algebraic equations, we consider singly-implicit methods to which are appended diagonally-implicit stages. Methods of this type are either similar to those of Butcher and Cash or else allow for the importation of a final derivative from a previous step. For these two classes, with up to three additional diagonallyimplicit stages, we derive methods that satisfy appropriate order conditions for index-2 DAEs.
J. C. Butcher, R. P. K. Chan