Christiansen, Jessie L.; Crossfield, Ian J. M.; Barentsen, Geert; Lintott, Chris J. (2018). “The K2-138 System: A Near-resonant Chain of Five Sub-Neptune Planets Discovered by Citizen Scientists”. The Astronomical Journal155 (2): 57. arXiv:1801.03874. Bibcode: 2018AJ....155...57C. doi:10.3847/1538-3881/aa9be0. ISSN1538-3881.
Hardegree-Ullman, Kevin K.; Christiansen, Jessie L.; Ciardi, David R. et al. (2021). “K2-138 g: Spitzer Spots a Sixth Planet for the Citizen Science System”. The Astronomical Journal161 (5): 219. arXiv:2102.08978. Bibcode: 2021AJ....161..219H. doi:10.3847/1538-3881/abeab0.
Christiansen, Jessie L.; Crossfield, Ian J. M.; Barentsen, Geert; Lintott, Chris J. (2018). “The K2-138 System: A Near-resonant Chain of Five Sub-Neptune Planets Discovered by Citizen Scientists”. The Astronomical Journal155 (2): 57. arXiv:1801.03874. Bibcode: 2018AJ....155...57C. doi:10.3847/1538-3881/aa9be0. ISSN1538-3881.
Hardegree-Ullman, Kevin K.; Christiansen, Jessie L.; Ciardi, David R. et al. (2021). “K2-138 g: Spitzer Spots a Sixth Planet for the Citizen Science System”. The Astronomical Journal161 (5): 219. arXiv:2102.08978. Bibcode: 2021AJ....161..219H. doi:10.3847/1538-3881/abeab0.
Christiansen, Jessie L.; Crossfield, Ian J. M.; Barentsen, Geert; Lintott, Chris J. (2018). “The K2-138 System: A Near-resonant Chain of Five Sub-Neptune Planets Discovered by Citizen Scientists”. The Astronomical Journal155 (2): 57. arXiv:1801.03874. Bibcode: 2018AJ....155...57C. doi:10.3847/1538-3881/aa9be0. ISSN1538-3881.
Hardegree-Ullman, Kevin K.; Christiansen, Jessie L.; Ciardi, David R. et al. (2021). “K2-138 g: Spitzer Spots a Sixth Planet for the Citizen Science System”. The Astronomical Journal161 (5): 219. arXiv:2102.08978. Bibcode: 2021AJ....161..219H. doi:10.3847/1538-3881/abeab0.
Hardegree-Ullman, Kevin; Christiansen, Jessie (January 2019). “K2-138 g: Spitzer Spots a Sixth Sub-Neptune for the Citizen Science System”. American Astronomical Society Meeting Abstracts #233233: 164.07. Bibcode: 2019AAS...23316407H.
Christiansen, Jessie L.; Crossfield, Ian J. M.; Barentsen, Geert; Lintott, Chris J. (2018). “The K2-138 System: A Near-resonant Chain of Five Sub-Neptune Planets Discovered by Citizen Scientists”. The Astronomical Journal155 (2): 57. arXiv:1801.03874. Bibcode: 2018AJ....155...57C. doi:10.3847/1538-3881/aa9be0. ISSN1538-3881.