References are vital for academic papers like research papers, dissertations, theses, etc. The first thing you should learn is how to select the required sources. The main mistakes students commit is using any web-site as a source in their papers. You should clarify with the tutor what sources are allowed for the specific assignment. Some might need only books, others can include web-sites, journals, etc. If you are free to select any sources relevant to your topic, you will definitely have a great choice.