When we look at any journal article, we see in the article's last section what is known as Reference. Reference is the term coined to describe the papers and books that were published and that were used to support the main arguments derived in the article. Reasoning and conclusions become possible due to the previous results listed in Reference.
Citing the sources and giving credit to the researchers that published the papers and books you have used in your research is key to advance the scientific knowledge.
"If I have seen further, it is by standing upon the shoulders of giants". Sir Isaac Newton