Give credit where credit is due. By properly citing the sources you use in your research projects you are both identifying the resources that you used to complete your work and you are formally acknowledging the authors or creators of those resources.
The most often used citation styles for the Performing Arts are MLA Handbook for Writers and the Chicago Manual of Style. Please consult your professor for the correct citation style to use.
You'll find many references in the course of your research. Make sure you keep track of what you find! Citation Management Systems are excellent tools to organize your references.