Wisser H, Knoll E
Clin Chim Acta. 1975 Feb 22;59(1):1-7. doi: 10.1016/0009-8981(75)90211-9.
The circadian rhythm of the excretion of the catecholamines and some main metabolites is investigated in five normal subjects and two patients with a high excretion. In the normal subjects there are remarkable differences in the amplitudes of the variables. At high catecholamine excretions these differences seem to disappear.