Kinematics of the outer halo of M 87 as mapped by planetary nebulae A. Longobardi, M. Arnaboldi, O. Gerhard, C. Pulsoni and I. Söldner-Rembold A&A, 620 (2018) A111 Published online: 05 December 2018 DOI: 10.1051/0004-6361/201832729