In general, you are all aware that you cite sources to avoid plagiarism. Because AI generated content is not coming from any single source, and because the training data cannot be attributed to any specific author, you cannot cite AI in the same way you might cite a scholarly article or website. This is why many academics and researchers are encouraging the practice of disclosure. Kari D. Weaver provides excellent rationale on the way in which generative-AI tools are affecting the traditional citation practices of higher education in her article "The Artificial Intelligence Disclosure (AID) Framework: An Introduction".
An excerpt...
"Within the contexts of education and research, and particularly within higher education, the citation has long been the standard tool for providing transparency and connection in the transfer of ideas across scholars, framing of arguments, and design of methodologies.
Unfortunately, citations do not fully meet the needs of today’s AI-enabled world. Citations emphasize the fixed form of a tangible output. This is incongruent with today’s generative AI systems, where the specific interplay of prompt, model, and model parameters creates a unique output that is not always repeatable, reproducible, or recallable, depending on the technology. Citations also focus on the ideas posed by an author, whereas generative AI can serve a variety of meaningful functions in the writing process, including researcher, editor, critic, collaborator, and more. While today’s citation practices do help provide some transparency, they are not sufficient, in and of themselves, to capture the varied ways AI tools function or are being used across contexts (Weaver 2024)."