@article{Ollero:95839,
      author        = "Ollero, A. and Ibisate, A. and Gonzalo, L. E. and Acín,
                       V. and Ballarín, D. and Díaz, E. and Domenech, S. and
                       Gimeno, M. and Granado, D. and Horacio, J. and Mora, D. and
                       Sánchez, M.",
      title         = "{The IHG index for hydromorphological quality assessment
                       of rivers and streams: updated version}",
      year          = "2011",
}