Currently, over 8,000 articles. 2012-, converted to wiki with peer-reviewed contributions. Original paper encylopedia in Math Reference, QA5 .M37213 1988, and a CD-ROM copy, QA5 .E59 1997 in Math Media.
Kieft, R & American Library Association (2008) Guide to Reference replaces the former Guide to Reference Books, published by the American Library Association in 1996. This new version offers expanded opportunities for searching, allowing the user to link to resources, compile lists, and take notes.