Reference for “XML Path Language (XPath) 2.0 (Second Edition)”

@TechReport{8361068,
  author      = "J\'{e}r\^{o}me Sim\'{e}on and Jonathan Robie and Don Chamberlin and Michael Kay and Mary F. Fern\'{a}ndez and Scott Boag and Anders Berglund",
  title       = "{XML} Path Language ({XPath}) 2.0 (Second Edition)",
  month       = apr,
  note        = "http://www.w3.org/TR/2009/PER-xpath20-20090421/",
  year        = "2009",
  bibsource   = "http://w2.syronex.com/jmr/w3c-biblio",
  type        = "{W3C} Proposed Edited Recommendation",
  institution = "W3C",
}