James Demmel Yozo Hida William Kahan Xiaoye S. Li Sonil Mukherjee E. Jason Riedy Error bounds from extra-precise iterative refinement. 325-351 2006 32 ACM Trans. Math. Softw. 2 http://doi.acm.org/10.1145/1141885.1141894 db/journals/toms/toms32.html#DemmelHKLMR06