Extracting Investor Sentiment from Weblog Texts: A Knowledge-based Approach. - Achim Klein; Olena Altuntas; Tobias Häusser; Wiltrud Kessler (CEC, 2011)

A Combined Approach for Extracting Financial Instrument-Specific Investor Sentiment from Weblogs. - Achim Klein; Olena Altuntas; Martin Riekert; Velizar Dinev (Wirtschaftsinformatik, 2013)