1Cross V. Fuzzy semantic distance measures between ontological concepts[J] IEEE Annual Meeting of the Fuzzy Information. 2004(2) :635-640.
2Roy Rada, Hafedh Mill, Ellen Bicknell, et al. Devel- opment and application of a metric on semantic nets [J] IEEE Transaction on Systems, Man, and Cyber-netics, 1989 : 19 (1) : 17-30.