Plagiarism is a very serious offense both in academic and professional world.
In order to avoid plagiarism, give credit whenever you use any type of information that others have created. The crediting consist of citations that connect the borrowed information to the original source of the information.
There are many citations styles in use, depending on the discipline or journal to publish your research. For your college papers, it is recommended to use the citation style recommended by your instructor. If there is no required style, pick one you are most familiar with and be consistent.
There is no general citation formatting style for engineering disciplines. Engineers utilize citation styles specific to their discipline as developed by their association (IEEE, ASCE, ASME, etc) or by journal publishers and editors. If there are no style requirements, use a citation style you are familiar with and be consistent.