Velocity asymmetries in young stellar object jets - Intrinsic and extrinsic mechanisms T. Matsakos, N. Vlahakis, K. Tsinganos, K. Karampelas, C. Sauty, V. Cayatte, S. P. Matt, S. Massaglia, E. Trussoni and A. Mignone A&A, 545 (2012) A53 Published online: 06 September 2012 DOI: 10.1051/0004-6361/201219498