Ani Nenkova Advaith Siddharthan Kathleen McKeown Automatically Learning Cognitive Status for Multi-Document Summarization of Newswire. 2005 conf/naacl/2005 HLT/EMNLP http://acl.ldc.upenn.edu/H/H05/H05-1031.pdf db/conf/naacl/naacl2005.html#NenkovaSM05