The ACS style guide : effective communication of scientific information. by 
Scientific Style and Format by For additional help in formatting your citations, visit these resources:
The ACS Style Guide recommends citing data sets retrieved from electronic databases as an online reference book or a website, with the URL or DOI and date accessed, followed by any additional identifying information. For example of a ChemSpider data sheet:
Royal Society of Chemistry. ChemSpider. http://www.chemspider.com/Chemical-Structure.2424.html (accessed June 15, 2011), Caffeine, CID=2424.
The GEO database has some requirements for citation that are very different from any of the others listed here. When you use the GEO, you must cite a paper about the database as a way of citing the database itself. Furthermore, if you use data sets, you should cite the original paper that the data producers wrote. The actual data sets should be referenced as in-text citations. GEO recommends a citation like this one:
"In March 2008, a search of the GEO Profiles database (Barrett et al., 2006) revealed that Gene X is upregulated in response to compound Y (GEO accession GDSxxx; Smith et al., 2006)."
For more information, visit the GEO citation guidelines here.
Often academic journals will expect authors to use their house style for citations. Always review a journal's guidelines before formatting your data citations. For example, if you are submitting an article to Nature, note that data sets are not cited in the references list. Rather, authors should cite an accession number and URL and these should be placed in the main text where they are discussed.
Data repositories like ICPSR, SEDAC and Dryad often request that they be credited in citations if you have used data sets from them.
Below are some more examples of citation guidelines from academic science journals and data repositories.
There is not yet a standard citation for data sets in CSE, so the format for books or Internet resources can be adapted. For example:
Sensenig A, Blackledge T, Agnarsson I. Silk tensile and web architecture measurements for 280 individuals and 22 species of Araneidae [Internet]. Dryad Digital Repository; [cited 2011 Jun 16]. Available from: http://dx.doi.org/10.5061/dryad.1827
CSE requires that you indicate the resource as being from the Internet and provide a date for the citation.
PubChem, which provides data on chemical compounds, substances, and bioassays, recommends that each compound be cited individiually in the following format:
National Center for Biotechnology Information. PubChem Compound Database; CID=2519, http://pubchem.ncbi.nlm.nih.gov/summary/summary.cgi?cid=2519 (accessed June 15, 2011).
