Seppelt R, Fath B, Burkhard B, Fisher JL, Grêt-Regamey A, Lautenbach S, Pert P, Hotes S, Spangenberg J, Verburg PH, van Oudenhoven APE (2012) Form follows function? Proposing a blueprint for ecosystem service assessments based on reviews and case studiesEcological Indicators 21: 145–154. http://www.sciencedirect.com/science/article/pii/S1470160X11002755