Usoskin, I.G.; Kromer, B.; Ludlow, F.; Beer, J.; Friedrich, F.; Kovaltsov, G.; Solanki, S.; Wacker, L. (2013). «The AD775 cosmic event revisited: the Sun is to blame». Astronomy and Astrophysics Letters552: L3. Bibcode:2013A&A...552L...3U. arXiv:1302.6897. doi:10.1051/0004-6361/201321080.
Nicolas Brehm, Marcus Christl, Timothy D. J. Knowles, Emmanuelle Casanova, Richard P. Evershed, Florian Adolphi, Raimund Muscheler, Hans-Arno Synal, Florian Mekhaldi, Chiara I. Paleari, Hanns-Hubert Leuschner, Alex Bayliss, Kurt Nicolussi, Thomas Pichler, Christian Schlüchter, Charlotte L. Pearson, Matthew W. Salzer, Patrick Fonti, Daniel Nievergelt, Rashit Hantemirov, David M. Brown, Ilya Usoskin & Lukas Wacker (7 de marzo de 2022). «Tree-rings reveal two strong solar proton events in 7176 and 5259 BCE». Nature Communications13 (1): 1196. Bibcode:2022NatCo..13.1196B. PMC8901681. PMID35256613. doi:10.1038/s41467-022-28804-9.
Usoskin, I.G.; Kromer, B.; Ludlow, F.; Beer, J.; Friedrich, F.; Kovaltsov, G.; Solanki, S.; Wacker, L. (2013). «The AD775 cosmic event revisited: the Sun is to blame». Astronomy and Astrophysics Letters552: L3. Bibcode:2013A&A...552L...3U. arXiv:1302.6897. doi:10.1051/0004-6361/201321080.
Nicolas Brehm, Marcus Christl, Timothy D. J. Knowles, Emmanuelle Casanova, Richard P. Evershed, Florian Adolphi, Raimund Muscheler, Hans-Arno Synal, Florian Mekhaldi, Chiara I. Paleari, Hanns-Hubert Leuschner, Alex Bayliss, Kurt Nicolussi, Thomas Pichler, Christian Schlüchter, Charlotte L. Pearson, Matthew W. Salzer, Patrick Fonti, Daniel Nievergelt, Rashit Hantemirov, David M. Brown, Ilya Usoskin & Lukas Wacker (7 de marzo de 2022). «Tree-rings reveal two strong solar proton events in 7176 and 5259 BCE». Nature Communications13 (1): 1196. Bibcode:2022NatCo..13.1196B. PMC8901681. PMID35256613. doi:10.1038/s41467-022-28804-9.
Usoskin, I.G.; Kromer, B.; Ludlow, F.; Beer, J.; Friedrich, F.; Kovaltsov, G.; Solanki, S.; Wacker, L. (2013). «The AD775 cosmic event revisited: the Sun is to blame». Astronomy and Astrophysics Letters552: L3. Bibcode:2013A&A...552L...3U. arXiv:1302.6897. doi:10.1051/0004-6361/201321080.
Nicolas Brehm, Marcus Christl, Timothy D. J. Knowles, Emmanuelle Casanova, Richard P. Evershed, Florian Adolphi, Raimund Muscheler, Hans-Arno Synal, Florian Mekhaldi, Chiara I. Paleari, Hanns-Hubert Leuschner, Alex Bayliss, Kurt Nicolussi, Thomas Pichler, Christian Schlüchter, Charlotte L. Pearson, Matthew W. Salzer, Patrick Fonti, Daniel Nievergelt, Rashit Hantemirov, David M. Brown, Ilya Usoskin & Lukas Wacker (7 de marzo de 2022). «Tree-rings reveal two strong solar proton events in 7176 and 5259 BCE». Nature Communications13 (1): 1196. Bibcode:2022NatCo..13.1196B. PMC8901681. PMID35256613. doi:10.1038/s41467-022-28804-9.