Use the citation format appropriate to the type of content and as is appropriate to your discipline or publisher. Use the PERMANENT LINK on the item's landing page, rather than the URL displayed in your browser. A handle (format: https://hdl.handle.net/1813/...) is always available, and for some items, a DOI (format: https://doi.org/10.7298/...) is also available. Both are persistent URLs. Do not link directly to individual files; these are not persistent URLs.
Several citation guides are available: https://www.library.cornell.edu/research/citation.