Shift working in the Chilean Andes (> 3600 m) and its influence on erythropoietin and low-pressure system. - Gunga,H.C.; Röcker,L.; Behn,C.; Hildebrandt,W.; Koralewski,E.; Rich,I.; Schobersberger,W.; Kirsch,K. (J Appl Physiol, 1996)