Levenshtein Distances Fail to Identify Language Relationships Accurately Simon J Greenhill author 2011-12 text journal article Computational Linguistics continuing MIT Press Cambridge, MA periodical academic journal greenhill-2011-levenshtein 10.1162/COLI_a_00073 https://aclanthology.org/J11-4003/ 2011-12 37 4 689 698