Information can be found in a variety of sources. The main two sources that you would be using are books (and ebooks) and peer-reviewed journal articles.

Books and ebooks

Books, specifically academic books give a broader overview on your topic. Books combine, condense, discuss and analyse information from a range of sources. Books are a good starting point for any research tasks.

Peer-Reviewed Journals and Articles

Peer-reviewed journals articles are articles written by scholars in their field and are reviewed by other scholars before they are published. 

Peer-reviewed articles focus on current research and are very specific. They are original, important and of a high standard.

In Primo, peer-reviewed articles have an icon saying it is PEER REVIEWED.

You can also check if the journal is peer-reviewed using Ulrichsweb global serials directory.