1. Matthes K, Ulmer W: Research on the analysis of the oxygen effect on patients with arterial hypoxemia. Dtsch Arch Klin Med 1955,202(5):548–58. (Article in German)
2. Ulmer WT, Prugger H, Bruck A: A fast recording oxygen measurement apparatus for continuous registration of oxygen concentration in the respiratory air. Pflügers Arch Gesamte Physiol Menschen Tiere 1960, 270: 536–9. (Article in German) 10.1007/BF00362223
3. Ulmer WT, Reichel G: Measurement of oxygen and carbon dioxide partial pressures in arterial and ear-lobe capillary blood with fixed micro-electrodes. Med Thorac 1963, 20: 235–49. (Article in German)
4. Podlesch I, Ulmer WT: Whole body plethysmography. Beitr Klin Erforsch Tuberk Lungenkr 1966,133(4):305–11. (Article in German) 10.1007/BF02120691
5. Ulmer WT, Hoffarth HP: Whole body plethysmography for determining intrathoracic gas volume. Pneumologie 1993,47(10):579–82. (Article in German)