V.  Beushausen, Roetmann, K., Schmunk, W., Wellhausen, M., Garbe, C. S., and Jähne, B., ?2D-measurement technique for simultaneous quantitative determination of mixing ratio and velocity field in microfluidic applications?, Imaging Measurement Methods for Flow Analysis, Results of the DFG Priority Programme 1147 Imaging Measurement Methods for Flow Analysis 2003-2009, vol. 106. Springer, p. 155--164, 2009.