Reference for “XML Path Language (XPath) 2.0”

@TechReport{Kay:07:XPL,
  author      = "Michael Kay and Don Chamberlin and Jonathan Robie and Mary F. Fern\'{a}ndez and J\'{e}r\^{o}me Sim\'{e}on and Scott Boag and Anders Berglund",
  title       = "{XML} Path Language ({XPath}) 2.0",
  month       = jan,
  note        = "http://www.w3.org/TR/2007/REC-xpath20-20070123/",
  year        = "2007",
  bibsource   = "http://w2.syronex.com/jmr/w3c-biblio",
  type        = "{W3C} Recommendation",
  institution = "W3C",
}