The nuclei of comets 7P/Pons-Winnecke, 14P/Wolf and 92P/Sanguin C. Snodgrass, A. Fitzsimmons and S. C. Lowry A&A, 444 1 (2005) 287-295 Published online: 21 November 2005 DOI: 10.1051/0004-6361:20053237