O.T. - as he signed - was an emblematic artist of the Gugging hospital, where he was interned because of the psychosis he began to suffer upon returning from the siege of Stalingrad. His drawings, antitheses of the horror vacui, are characterized by their minimalism, the purity, the economy of means and effects, the sense of balance and space. Admired by Michel Thévoz, who devoted several feature articles to him, he also fascinated David Bowie and Brian Eno, who met and collected him. His works can be found in countless collections, such as those of Arnulf Rainer (Austria), abcd/Bruno Decharme (France) or the Pinacothèque Hervé Lancelin (Luxembourg).