Hattam, Caroline, Atkins, Jonathan P., Beaumont, Nicola, Börger, Tobias, Böhnke-Henrichs, Anne, Burdon, Daryl, de Groot, Rudolf, Hoefnagel, Ellen, Nunes, Paulo A. L. D., Piwowarczyk, Joanna, Sastre, Sergio, Austen, Melanie C., "Marine ecosystem services: Linking indicators to their classification", Ecological indicators, 2015