A. Johann Wilhelm Ludwig von Luce (1750–1842), the German priest and scholar, engaged in propagation of Estonian language, who first described the Kaali lake crater in 1827 (https://utlib.ut.ee/eeva/index.php?lang=de&do=autor_pilt&aid=85&eid=37). B. Title page of his work on the Oesel Island, containing first account on the crateriform structure. C. The oldest location plan of the Kaalijärv crateriform structure published in an archaeological monograph of Kruse (1842, pl. 62), who probably introduced this name (as KaliJerw) to scientific literature (Wangenheim von Qualen, 1849, p. 36).