Binary central stars of planetary nebulae with long orbits: the radial velocity orbit of BD+33°2642 (PN G052.7+50.7) and the orbital motion of HD 112313 (PN LoTr5)
Hans Van Winckel, Alain Jorissen, Katrina Exter, Gert Raskin, Saskia Prins, Jesus Perez Padilla, Florian Merges and Wim Pessemier
