Variational principles and the effect of a cutoff on population pattern size V. Méndez, W. Horsthemke, J. Casas-Vázquez and E. P. Zemskov Eur. Phys. J. Special Topics, 146 (2007) 189-197 Published online: 05 July 2007 DOI: 10.1140/epjst/e2007-00179-6