Data requires citations for the same reasons journal articles and other types of publications require citations: to acknowledge the original author/producer and to help other researchers find the resource.
Unfortunately, standards for the citation of data are not uniformly agreed upon and have yet to be codified by the National Information Standards Organization (an organization that sets technical standards for other bibliographic materials)
This guide provides guidance on how to construct a citation for data. Doing so is important to acknowledge the work of others if the data is not your own, but even if it is your own to enable others to find (and perhaps re-use) your data.
Because few citation style guides offer guidance on how to cite data, this set of reccommendations should not be taken as the final word on styles. If you have a question, check with your faculty advisor or the journal in which you hope to publish.
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