Hulshof, C. T., Verbeek, J. H., van Dijk, F. J., van der Weide, W. E., & Braam, I. T. (1999). Evaluation research in occupational health services: General principles and a systematic review of empirical studies. BMJ Group.

Hulshof, C. T., J. H. Verbeek, F. J. van Dijk, W. E. van der Weide, و I. T. Braam. Evaluation Research in Occupational Health Services: General Principles and a Systematic Review of Empirical Studies. BMJ Group, 1999.

Hulshof, C. T., et al. Evaluation Research in Occupational Health Services: General Principles and a Systematic Review of Empirical Studies. BMJ Group, 1999.