,
doi.org/10.1016/j.jcss.2010.06.018
ScienceDirect - Article in Press
Algorithms and Complexity

Terwijn, S. A., Torenvliet, L., & Vitányi, P. (2010). Nonapproximability of the Normalized Information Distance. ScienceDirect - Article in Press. doi:10.1016/j.jcss.2010.06.018