Reference:
  Author: Alexei J Drummond and Andrew Rambaut
  Title: "BEAST: Bayesian evolutionary analysis by sampling trees"
  Journal: BMC Evol Biol
  Year: 2007
  Volume: 8
  Number: 7
  Pages: 214
  DOI: 10.1186/1471-2148-7-214
  PMID: 17996036
  URL: http://www.biomedcentral.com/1471-2148/7/214/abstract
  eprint: http://www.biomedcentral.com/content/pdf/1471-2148-7-214.pdf
