Rudolf Heuer, Hans Irschik, Franz Ziegler,
"Nonlinear Free Vibrations of Shallow Shells: A Unifying Formulation."
, in I. Troch, F. Breitenecker: Proc. of the 1. Mathmod, Vienna 1994, Vienna: Technical University, 1994
Original Titel:
Nonlinear Free Vibrations of Shallow Shells: A Unifying Formulation.