A quantitative study of O stars in NGC 2244 and the Monoceros OB2 association, Martins, F.; Mahy, L.; Hillier, D. J.; Rauw, G., Astronomy and Astrophysics538, pp. A39, Bibcode:2012A&A...538A..39M, doi:10.1051/0004-6361/201117458.
A quantitative study of O stars in NGC 2244 and the Monoceros OB2 association, Martins, F.; Mahy, L.; Hillier, D. J.; Rauw, G., Astronomy and Astrophysics538, pp. A39, Bibcode:2012A&A...538A..39M, doi:10.1051/0004-6361/201117458.
Almendros-Abad, V.; Mužić, K.; Bouy, H.; Bayo, A.; Scholz, A.; Peña Ramírez, K.; Moitinho, A.; Kubiak, K.; Schöedel, R.; Barač, R.; Brčić, P.; Ascenso, J.; Jayawardhana, R. (2023-05-01). "Spectroscopic substellar initial mass function of NGC 2244". {{cite journal}}: Cite journal requires |journal= (help)