Two-sided radio emission in ON 231 (W Comae) E. Massaro, F. Mantovani, R. Fanti, R. Nesci, G. Tosti and T. Venturi A&A, 374 2 (2001) 435-442 Published online: 15 August 2001 DOI: 10.1051/0004-6361:20010754