121422615
Flächenapproximation beim Jacobialgorithmus
120952401
The measure of the set of admissible lattices
A0 denotes the lattice of points with integral coordinates. Theorem 4 will be used to prove Theorem 5 which is an improvement of the Minkowski-Hlawka Theorem. We also prove two existence theorems which are in a certain sense converses of the MinkowskiHlawka Theorem (Theorem 6 and Theorem 7). The author is very indebted to the referee who pointed out some errors of the originally submitted paper and made useful suggestions. The originally stated Theorem 1 was wrong.
122689116
On simultaneous approximations of two algebraic numbers by rationals
120328164
Irregularities of distribution. IV
123201234
Badly approximable systems of linear forms
A number α is called badly approximable if there is a constant c = c(α)>0 such that 
|q|αq − p| > c(α) 
for any integers p, q ≠ 0. The existence of continuum—many badly approximable numbers follows easily from the theory of continued fractions. In the present paper the notion of a badly approximable number is generalized to badly approximable systems of m linear forms in n variables. Among other results we prove for every given m and n the existence of continuum many badly approximable systems of linear forms.
121164029
Über höhere kritische Determinanten von Sternkörpern
121073876
Existence of solutions of certain nonconvex optimal control problems governed by nonlinear integral equations
Optimal control problems with nonlinear equations usually do not have a solution, i.e. an optimal control. Nevertheless, if the cost functional is uniformly concave with respect to the state, the solution may exist. Using the Balder's technique based on a Youngmeasure relaxation, Bauer's external principle and investigation of extreme Young measures; the existence is demonstrated here for optimal control processes described by nonlinear integral equations