Exploring the bulk of the BL Lacertae object population - I. Parsec-scale radio structures E. Liuzzo, M. Giroletti, G. Giovannini, B. Boccardi, S. Tamburri, G. B. Taylor, C. Casadio, M. Kadler, G. Tosti and A. Mignano A&A, 560 (2013) A23 Published online: 29 November 2013 DOI: 10.1051/0004-6361/201322144