Asymmetric transition disks: Vorticity or eccentricity? S. Ataiee, P. Pinilla, A. Zsom, C. P. Dullemond, C. Dominik and J. Ghanbari A&A, 553 (2013) L3 Published online: 29 April 2013 DOI: 10.1051/0004-6361/201321125