van Praag, B. M. S., Slootman, K., Stam, P. J. A., van Ophem, J. C. M., Wijnbergen, W., & van Praag, C. M. (1996). The demand for concerts of classical music-decision support for the scenario-planning of orchestras by means of ROA-analysis. Marketing and Research Today, 24, 27-35.