Citation Databases

Web of Science (Subscription through B-ON)
consists of seven databases containing information gathered from thousands of scholarly journals, books, book series, reports, conferences, and more.
The first three citation databases contain the references cited by the authors of the articles. You can use these references to do cited reference searching. This type of search allows you to find articles that cite a previously published work.

Scopus (UNL Subscribes this resource)
is an abstract and citation database of research literature including peer-reviewed titles, Open Access journals, conference proceedings, trade publications, patent records, scientific web pages, and seamless links to full text articles.

PubMed - National Library of Medicine (Free database)

is a free database with content of biomedical literature from MEDLINE, life sciences journals and online books.

Google Scholar
provides a simple way to broadly search for scholarly literature. From one place, you can search across many disciplines and sources: articles, theses, books, abstracts and court opinions, from academic publishers, professional societies, online repositories, universities and other web sites. Google Scholar helps you find relevant work across the world of scholarly research.

Publish or Perish
is a software program that retrieves and analyzes academic citations. It uses Google Scholar to obtain the raw citations, then analyzes these and presents statistics.