Uchikawa, Y., Cowley, L., Hayakawa, H., Willis, D. M., & Stephenson, F. R. (2020). Provenance of the cross sign of 806 in the Anglo-Saxon Chronicle: a possible lunar halo over continental Europe?. History of Geo- and Space Sciences, 11(1), 81-92. https://doi.org/10.5194/hgss-11-81-2020