Not free, but provided by the university to all members of the NU community. Two very powerful programs that let you save citations, insert those citations into your paper, and automatically create a works cited at the end.
There is a whole world of software out there designed to help you keep track of your research, and turn those citations into well-formatted bibliographies and works cited.
Always check with your professor to see if there is a required style for your paper. In general, researchers in English and American literature use the Modern Language Association (MLA) citation style, or possibly the Notes-Bibliography version of the Chicago Manual of Style.
The NU Academic Integrity Policy defines plagiarism as "intentionally representing the words, ideas, or data of another as one’s own in any academic exercise without providing proper citation."
Since it is a serious violation of intellectual integrity, plagiarism harms the reputation of the university as well as the individual.
For more information, see our guide to Avoiding Plagiarism.