A citation is a shorthand way of referring to an information source. Citations are also called references. Research articles and conference papers (as well as other sources such as dissertations and many books) have - at the end - a list of citations that the author referred to. Citations consist of all the information required so anyone could track down the full text of that particular source. There are many different "styles" for writing citations. These styles dictate the order and formatting elements such as the title, publication year, volume, issue, authors, etc.
Articles, conference papers, and books found online (in an electronic format) are not considered websites and should not be cited as if they are websites.
Engineering students at NAU are usually asked to cite their sources using IEEE (Institute of Electrical and Electronics Engineers) style. The IEEE is a professional organization supporting many branches of engineering, computer science, and information technology. In addition to publishing journals, magazines, and conference proceedings, IEEE also makes standards for a wide variety of industries.
IEEE citation style includes in-text citations, numbered in square brackets, which refer to the full citation listed in the reference list at the end of the paper. The reference list is organized numerically, not alphabetically.
Here are some style guides that will help you format your citations: