H. Beelitz, S. Levy, R. Linhardt, and H. Miller. AFIPS Fall Joint Computing Conference, volume 31 of AFIPS Conference Proceedings, page 185-200. AFIPS / ACM / Thomson Book Company, Washington D.C., (1967)
T. Beelitz, C. Bischof, B. Lang, and K. Althoff. Numerical Software with Result Verification, volume 2991 of Lecture Notes in Computer Science, page 198-205. Springer, (2003)