1. Dbpedia: A nucleus for a web of open data;Auer,2007
2. Yago-a Core of Semantic Knowledge;Kasneci,2006
3. Freebase: a collaboratively created graph database for structuring human knowledge;Bollacker,2008
4. Machine learning in automated text categorization;Sebastiani;ACM Comput. Surv.,2002
5. Thumbs up?: sentiment classification using machine learning techniques;Pang,2002