Mid-range natural orbits around the triple asteroid 2001SN263 M.P.O. Cavalca, V.M. Gomes and D.M. Sanchez Eur. Phys. J. Special Topics, 229 8 (2020) 1557-1572 Published online: 29 May 2020 DOI: 10.1140/epjst/e2020-900093-0