Q: Do I need to provide a citation for an existing theory?

You have three questions, all around the same point. All the same, let’s handle the three questions separately and one by one.

Do you need to cite the theory?

For established theories, such as this one, no, you do not need to provide a citation. You are fine with just mentioning the theory. In case the theory had been founded by someone or a group of people who are closely associated with the theory, you could mention their names. For example, consider Maslow’s Hierarchy of Needs. The postulation of the Hierarchy of Needs is so closely linked with its originator Abraham Maslow that his name is often included before the theory. (Of course, later on in the paper, his name is dropped as it would then get too repetitive.) Newton’s Laws of Motion, on the other hand, are often referred to simply on their own. Queuing theory doesn’t seem to have a name associated with it. If it does, you could of course include it (them); if not, you of course don’t need to include any name.

Will your reference to the theory be deemed as a citation?

No, if you are simply referring to the theory, it won’t be considered a citation. If however you are referring to some other paper and what they have said about the theory or how they have used it, that of course would need to be a citation. That is, you would need to cite the referenced paper (and the author/s) rather than the original theory.

Do you need to include citations for a well-known theory?

As we have already discussed in the earlier questions, no, you don’t need to provide citations unless you are referring to some other paper that has said something (new) about the original theory.

If needed, you may look up related papers to see how they have handled this scenario.

On our site, for more insights into citations/references, you may refer to the following resources:

• How should I cite a reference that I found in a paper?
• Citing books as a source of information
• How to provide correct citations and references for your research [Course]

Hope that helps. All the best for your work on queuing theory!