Google Scholar - Google Scholar is a freely accessible web search engine that indexes the full text of scholarly...
PubMed.gov - PubMed comprises more than 29 million citations for biomedical literature from MEDLINE, life science journals, and online books. Citations may include links to full-text content from PubMed Central and publisher web sites.
EasyBib - Automatic works cited and bibliography formatting for MLA, APA and Chicago/Turabian citation styles.
Hubmed - An alternative interface to the PubMed medical literature database.
Academia.edu - Academia is a website where you can share papers that are written with other users. You can use a Google or Facebook account to sign in to the website.
SemanticScholar - An academic search engine that utilizes artificial intelligence methods to provide highly relevant results and novel tools to filter them with ease.