@article{Guzik:2013,
  author  = "P. Guzik and B. Zuchowski and K. Blaszyk and W. Seniuk and M. Wasniewski and A. Gwizdała and A. Wykrętowicz and J. Piskorski",
  title   = "Asymmetry of the variability of heart rate and conduction time between atria and ventricles",
  journal = "Circulation Journal",
  volume  = "Vol. 77",
  number  = "no. 12",
  pages   = "2904--2911",
  year    = "2013",
}