Witt, Detlev MPI for Comparative and International Private Law, Max Planck Society;
https://max-eup2012.mpipriv.de/index.php/Association_Agreements (beliebiger Volltext)
Witt, D. (2012). Association Agreements. In J. Basedow, K. J. Hopt, & R. Zimmermann (Eds.), Max Planck Encyclopedia of European Private Law (pp. 80-85). Oxford: Oxford University Press.