author        = "Virues-Ortega, J. and Vega, S. and Seijo-Martinez, M. and
                       Saz, P. and Rodriguez, F. and Rodriguez-Laso, A. and de Las
                       Heras, S.P. and Mateos, R. and Martinez-Martin, P. and
                       Mahillo-Fernandez, I. and Garre-Olmo, J. and Gascon, J. and
                       Garcia-Garcia, F.J. and Fernandez-Martinez, M. and
                       Bermejo-Pareja, F. and Bergareche, A. and Benito-Leon, J.
                       and de Pedro-Cuesta, J.",
      title         = "{A protective personal factor against disability and
                       dependence in the elderly: an ordinal regression analysis
                       with nine geographically-defined samples from Spain}",
      year          = "2017",