1. Alexander RR, Shields S (2003) Using land as a control variable in density-dependent bioeconomic models. Ecol Model 170: 193–201
2. Ando A, Getzner M (2005) The roles of ownership, ecology, and economics in public wetland-conservation decisions. Ecol Econ 58(2): 287–303
3. Begon M, Harper JL, Townsend CR (1996) Ecology. Individuals, populations and communities, 3rd edn. Blackwell, Malden
4. Behrens D, Friedl B, Gebetsroither B, Getzner M, Lieb S (2006) Optimal dynamic nature conservation strategies. Final report to the Jubiläumsfonds der Oesterreichischen Nationalbank (Austrian Central Bank), project No. 11216, Klagenfurt/Graz
5. BirdLife International (2004) Birds in Europe: population estimates, trends and conservation status, Birdlife Conservation Series, vol 12. Birdlife International, Cambridge