From the expert opinion of PhDr. Rea Michalová Ph.D.: "The reviewed artwork "Ballet performance" is an authentic, high-quality, very rare collector's item, intrinsically lyrical, and the most typical work of Jiří Trnka, an artist of the Renaissance character "uomo universale" the fields of painting, drawing, graphics, illustration, puppetry, sculpture and animated film. The artist's name became an international term with the "made-in" brand, so universal that it surpassed even the sound of the most popular sportsmen or later even singers. The legendary French poet, painter and filmmaker Jean Cocteau said about the author: "Trunk - this is the kingdom of childhood and poetry." The work Ballet performance reflects the author's genius painterly lightness, the airiness of impressively felt brushstrokes, color-rounded by an unusually noble earthy palette. Both the author's typical painterly "gusto" (as he himself said) and an unusual personal preoccupation, reflected not only in the painterly tenderness, but also in the choice of motif, come into play here. The artistic generation to which Trnka belonged was literally attracted to the subject of theater magical."