The references to someone else's work that you use to support your ideas are important to your argument and must be of the best possible quality. They may come under scrutiny as much as your own research.
Your own judgment is important, but some basic ways to judge the quality of any resource are outlined in Resource Evaluation (Morningside College). Remember that scholarly resources report the results of research for an audience of scholars and researchers. Look for any gaps in methodologies, repetition and irrelevant citations.
If you are looking at another author's references, a simple way to evaluate these is to look at the number of citations to an article. However you may also like to read the article Why (almost) everything we know about citations is wrong: Evidence from authors (M. Teplitskiy, E. Duede, M. Menietti, K. Lakhani, 2018).
You can also check the quality of the journal in which the article was published. Standard measures (journal metrics) have used a range of methods. For detailed guidance see our How to find standard journal metrics guide.
Cabells Scholarly Analytics will also help you judge the quality of journals.