H. Middelkoop

Ambulatory activity monitoring during sleep: an evaluation of internight and intrasubject variability in healthy persons aged 50-98 years.

H. Kamphuisen, H. Middelkoop, E. van der Velde, 1993, Sleep.

The prevalence of clinically significant sleep apnoea syndrome in the Netherlands

B Kemp, B. Kemp, H. Kamphuisen, 1998, Thorax.

Bradykinesia and hypokinesia in Parkinson's disease: what's in a name?

R. A. C. Roos, J. J. van Hilten, A. A. van Eerd, 1998, Journal of Neural Transmission.

Diurnal effects of motor activity and fatigue in Parkinson's disease.

R. Roos, H. Middelkoop, E. van der Velde, 1993, Journal of neurology, neurosurgery, and psychiatry.