1. CELEX Lexical Database of English (version 2.5) . 1995 . Centre for Lexical Information, Max Planck Institute for Psycholinguistics, Nijmegen . ( Baayen 1995 ).
2. The Brooklyn-Geneva-Amsterdam-Helsinki Parsed Corpus of Old English . 2000 . ( Pintzuk 2000 ).
3. The Penn-Helsinki Parsed Corpus of Middle English . 2000 . ( Kroch & Taylor 2000 ).
4. Historical and Comparative Linguistics