E. V. Ukhanova, M. N. Zhizhin, and A. V. Andreev, “New Results of Visualization of the Lost Miniatures of the Khludov Psalter of the Middle of the 9th Century by Natural Science Methods”, APTHA, vol. 11, pp. 244–255, Oct. 2021, doi: 10.18688/aa2111-02-20.