Quality research is based on evidence. It is important to cite sources to support your research conclusions. There are many different formats, with APA, MLA, and Chicago being the most common. There are also citation generators which will format your citation in a specified format. No matter what you use, CHECK your citations for accuracy and correct formating. Also, there may not be a sample format for all kins of sources, so you may have to adapt your citation to the spirit of the particular style.
Citation Sources is a subject guide that provides sample citations for each of the major styles.