Nels Benson

A Grammar Inference Algorithm for the World Wide Web

Oren Etzioni, Terrance Goan, Stottler Henke, 2002 .

KeyGraph : Automatic Indexing by Segmenting and Unifing Co-Occurrence Graphs

Yukio Ohsawa, Masahiko Yachida, Nels Benson, 1999 .