1. Uber eine Methode zur Registrierung der Volumanderungen des Herzens am Menschen;Keidel;Z Kreislaufforsch,1950
2. Use of ultrasonic reflectoscope for continuous recording of movements of heart walls;Edler;Kungl Fysiogr Sallsk Lund Forhandl,1954
3. Ultrasonic echo method in cardiological diagnosis;Effert;Germ Med Methods,1957
4. Ultrasonic cardiography in mitral defect and in nonpathological heart;Schmitt;Z Kreislaufforsch,1960
5. Ultrasonic cardiogram in mitral stenosis;Edler;Acta Med Scand,1957