Warning - the bibtex entry below may be invalid: 
Missing 'institution' field 
@techreport{RSA Threshold Signature,
  author = "Long Hoang Nguyen",
  booktitle = "Oxford computing technical report, URL: http://web.comlab.ox.ac.uk/oucl/publications/tr/",
  journal = "Oxford computing technical report",
  title = "Partially Interactive Threshold RSA Signatures",
  url = "http://www.comlab.ox.ac.uk/people/long.nguyen/Threshold.pdf",
  year = "2005, Oxford computing technical report",
}