Information on CIF and the COMCIFS committee may be found at http://www.iucr.org/iucr-top/cif/home.html
The original paper describing the CIF format is:
mmCIF (macromolecular Crystallographic Information File) is an extension of the original CIF concept to support the added complexity of very large macromolecular structures.
For information on mmCIF see:
Philip E. Bourne and Helen M. Berman and Brian McMahon and Keith D. Watenpaugh and John Westbrook and Paula M. D. Fitzgerald. Methods in Enzymology, 277, Charles W. Carter and Robert M. Sweet, editors. Macromolecular Crystallography, Part B "The Macromolecular Crystallographic Information File (mmCIF)". Academic Press, 1997.For the mmCIF home page click here.
PowderCIF is an extension to cover items particular to powder diffraction data. Information on the PowderCIF dictionary can be found at http://www.iucr.org/cif/pd/index.html.
CIF is copyrighted by the IUCr to protect the usage of the format for the whole community whilst allowing free usage. See the IUCr official statement of policy on the use of CIF/STAR.