1. Abel H-H, Klüssendorf D, Koepchen H-P (1989) Relation between tone and rhythmicity of cardiac chronotropic innervation. Pflügers Arch 413:R11
2. Abel HH, Klüssendorf D, Koralewski E, Krause R, Droh R (1992) Spectral analysis of heart rate during different states of activity. In: Schmidt THF, Engel BT, Blümchen G (eds) Temporal variations of the cardiovascular system. Springer, Berlin Heidelberg New York, pp 100–116
3. Bleecker, ML, Bolla KI, Agnew J, Schwartz BS, Ford DP (1991) Dose-related subclinical neurobehavioral effects to chronic exposure to low levels of organic solvents. Am J Ind Med 19:715–728
4. Habilitationsschrift;K Eckoldt,1975
5. Eckoldt K (1984) Verfahren und Ergebnisse der quantitativen automatischen Analyse der Herzfrequenz und deren Spontanvariabilität. Dtsch Gesundheitswes 39:856–863