Science fields are centered around sources just like any other field. Using them in your papers is essential to show how your thinking builds on the scholarship of your field. However, the sources function differently because of the importance of experimentation. As a result, sources are not treated equally in terms of their authority: peer-reviewed primary research articles are the most highly valued. Peer-reviewed review articles are also highly valued.
Types of Published Sources
Peer-reviewed primary research articles
Peer-reviewed review articles
Chapters in edited books
Books from university or popular presses
Websites maintained by government agencies or foundations that collate descriptive statistics (like the NIH or the CDC)