Snodgrass, C. Department Planets and Comets, Max Planck Institute for Solar System Research, Max Planck Society;
Epifani, E. M., Perna, D., Di Fabrizio, L., Dall'Ora, M., Palumbo, P., Snodgrass, C., et al. (2014). Observational results for eight long-period comets observed far from the Sun. Astronomy and Astrophysics, 561: A6. doi:10.1051/0004-6361/201321290.