1. http://purl.oclc.org/metadata/dublin_core
2. http://purl.oclc.org/metadata/dublin_core_elements
3. http://www.oclc.org/oclc/press/971107a.htm Nov. 7, 1997
4. [DSIG] W3C Digital Signature Working Group http://www.w3.org/DSig/
5. http://www.imsproject.org