"a web search engine for students and researchers that aims to make academic information easily accessible to everyone. RefSeek searches more than one billion documents, including web pages, books, encyclopedias, journals, and newspapers."
Google Scholar is a free online search engine that allows one to search for peer-reviewed articles, books, and other resources. Great source if unable to access a database. Recommended as a starting point when researching a topic.
"Pew Research Center is a nonpartisan fact tank that informs the public about the issues, attitudes and trends shaping America and the world. We conduct public opinion polling, demographic research, content analysis and other data-driven social science research. We do not take policy positions."