• A unified classification of alien species based on the magnitude of their environmental impacts 

      Blackburn, Tim M.; Essl, Franz; Evans, Thomas; Hulme, Philip E.; Jeschke, Jonathan M.; Kuhn, Ingolf; Kumschick, Sabrina; Markova, Zuzana; Mrugala, Agata; Nentwig, Wolfgang; Pergl, Jan; Pysek, Petr; Rabitsch, Wolfgang; Ricciardi, Anthony; Richardson, David M.; Sendek, Agnieszka; Vila, Montserrat; Wilson, John R. U.; Winter, Marten; Genovesi, Piero; Bacher, Sven (PLoS, 2014)
      Species moved by human activities beyond the limits of their native geographic ranges into areas in which they do not naturally occur (termed aliens) can cause a broad range of significant changes to recipient ecosystems; ...