1. Ästrand, P. O.: Experimental studies of physical working capacity in relation to sex and age. Kopenhagen 1952
2. Âstiand, J.: Aerobic work capacity in men and woman with special reference to age. Acta physiol. Scand. 49 (1960) Suppl. 169
3. Balke, B. : Optimale körperliche Leistungsfähigkeit, ihre Messung und Veränderung infolge Arbeitsermüdung. Arbeitsphysiol. 15 (1952), S. 311
4. Bengtsson, E.: The working capacity in normal children, evaluated by submaximal exercise on the bycicle ergometer and compared with adults. Acta med. Scand. 154 (1956), S. 359
5. Bock, A. V.; Vancaulaert, C.; Dill, D. B.; Fölling, A; Hurxthaler, L. M.: J. Physiol. 66 (1928)