1. Design and experimental results for the S809 airfoil
2. van Ingen, J. L. "A suggested Semi-Empirical Method for the Calculation of the Boundary Layer Transition Region," Department of Aerospace Engineering, Delft University of Technology, Report VTH-74,1956. (a) Row A, = 0.163 (b) Row B, = 0.252 (c) Row C, = 0.370