- Ulbrich, U., and P. Speth (1992): A baroclinic instability criterion used as a diagnostic tool for climate and climate simulations. Annales Geophysicae, Suppl. II to Vol. 10, C252.
- Ulbrich, U., and P. Speth (1992): Diagnosis of baroclinic instability. Second international conference on modelling of global climate change and variability, Abstracts. Max-Planck-Institut für Meteorologie, p. 132.