Inhalt:W. LARCHER: Altitudinal Variation in Flowering Time of Lilac (Syringa vulgaris L.) in the Alps in Relation to Temperatures;F. SCHWEIGER: A Note on the Eigenvalues for Periodic Three-Dimensional Jacobi-Perron Algorithms;J. KOSINKA - B. JUTTLER: Cubic Helices in Minkowski Space;E. HLAWKA: Pythagoraische Tripel hoherer Ordnung;B.J. GRUBER: Mathematical-Physical Properties of Musical Tone Systems II: Applications;A. HOFINGER: The Metrics of Prokhorov and Ky Fan for Assessing Uncertainty in Inverse Problems;W. Jab Lo Nski - L. REICH: Stability of the Translation Equation in Rings of Formal Power Series and Partial Extensibility of One-Parameter Groups of Truncated Formal Power Series;J. CIGLER: Remarks on Some Sequences of Binomial Sums;B. ODEHNAL: Die Linienelemente des P3;G. LARCHER - F. PILLICHSHAMMER: An Extremum Problem for Convex Polygons;C. HEUBERGER - A. PETHO - R.F. TICHY: Thomas' Family of Thue Equations over Imaginary Quadratic Fields, II;S.J. BAUER: Electron Density Distribution in the Topside Ionosphere of Mars and Associated Atmospheric Parameters