Hackbusch, W., Wittum, G., Hackbusch, W., Hackbusch, W., & Wittum, G. (1998). Multigrid methods V: Proceedings of the Fifth European Multigrid Conference, held in Stuttgart, Germany, October 1-4, 1996. New York: Springer-Verlag.

Hackbusch, W., Gabriel Wittum, W. Hackbusch, Wolfgang Hackbusch, and Gabriel Wittum. Multigrid Methods V: Proceedings of the Fifth European Multigrid Conference, Held in Stuttgart, Germany, October 1-4, 1996. New York: Springer-Verlag, 1998.

Hackbusch, W., et al. Multigrid Methods V: Proceedings of the Fifth European Multigrid Conference, Held in Stuttgart, Germany, October 1-4, 1996. New York: Springer-Verlag, 1998.