Dear Christophe,
I like to cite pyneb on a future paper. The first refereed paper on pyneb is paper I. I see a note on paper I that asks us to quote paper II as well, but I could not find a paper II in the lit.
Paper I being: \bibitem[Luridiana et al.(2015)]{2015A&A...573A..42L} Luridiana, V., Morisset, C., \& Shaw, R.~A.\ 2015, \aap, 573, A42. doi:10.1051/0004-6361/201323152
If paper I is sufficient, no need to reply.
Thank you! Sending best regards,
Letizia