@PHDTHESIS {ABELE:2003a, title = {Social security systems and demographic developments in agriculture in the CEE candidate countries}, author = {Abele, S. and Frohberg, K. and Hartmann, M. and Matthews, A. and Weingarten, P. }, year = {2003}, school = {European Economic. Directorate General for Agriculture}, note = {European Commission-Directorate General for Agriculture, Brussels, Belgium}, }