1. A stability property of implicit Runge-Kutta methods;Butcher;Nordisk Tidskr. Informationsbehandling,1975
2. On the implementation of implicit Runge-Kutta methods;Butcher;Nordisk Tidskr. Informationsbehandling,1976
3. A special stability problem for linear multistep methods;Dahlquist;Nordisk Tidskr. Informationsbehandling,1963