Do you have the DOI (direct object identifier) for the resource (article, book chapter, or book) and need to locate it online? Resolve the DOI name at https://www.doi.org/ and it will take you directly to the the current URL.
Sources that do not undergo a "peer review" process are not typically considered as an academic resources are listed below... They can however be used as a starting point for your research. Be sure to verify any information obtained from these resources using reliable library sources.
These database sources are your best bets for finding biology related literature. Click on any link to take you directly to the database homepage.