Unbiased group-wise alignment by iterative central tendency estimations M. S. De Craene, B. Macq, F. Marques, P. Salembier and S. K. Warfield Math. Model. Nat. Phenom., 3 6 (2008) 2-32 Published online: 24 December 2008 DOI: 10.1051/mmnp:2008079