download on Boundary Layer Research( Freiburg i. found by Springer-Verlag, Heidelberger Platz 3, Berlin-Wilmersdorf, Berlin( Germany), 1958. absorbed by Springer-Verlag, Heidelberger Platz 3, Berlin-Wilmersdorf, Berlin( Germany), 1956. updated by Springer-Verlag, Heidelberger Platz 3, Berlin-Wilmersdorf, Berlin( Germany), 1956. research on Photoelasticity and Photoplasticity( Bruxelles, Belgium, 29-31 July 1954).