Harmonization of the assessment method for classifying the ecological quality status of very large Greek riversMaria Lazaridou, Chrysoula Ntislidou, Ioannis Karaouzas, Nikolaos Skoulikidis and Sebastian BirkKnowl. Manag. Aquat. Ecosyst., 419 (2018) 50DOI: https://doi.org/10.1051/kmae/2018038