Duelli, P., Obrist, M.K. (2003): Monitoring biodiversity in agricultural landscapes: the dilemma of conflicting value systems and indicators. In: Segers, H., Branquart, E., Caudron, A., Tack, J. (eds): Scientific Tools for Biodiversity Conservation: Monitoring, Modelling and Experiments. Proc. 5th Meeting of the European Platform for Biodiversity Research Strategy, 2-4 December 2001, Brussels. 170-174.
Duelli, P., Obrist, M.K. (2003):Regional biodiversity in an agricultural landscape: the contribution of seminatural habitat islands. Basic Appl. Ecol., 4: 129–138.