Reference for “Portable Network Graphics (PNG) Specification (Second Edition)”

@TechReport{Duce:03:PNG,
  author      = "David Duce",
  title       = "Portable Network Graphics ({PNG}) Specification (Second Edition)",
  month       = nov,
  note        = "http://www.w3.org/TR/2003/REC-PNG-20031110",
  year        = "2003",
  bibsource   = "http://w2.syronex.com/jmr/w3c-biblio",
  type        = "{W3C} Recommendation",
  institution = "W3C",
}