Geodesic

Three-dimensional periodic orbits and their stability
p. 1-22
Sur la linearizsation d΄un systeme differentiel du type de Riccati
p. 31-33
On some mathematical aspects of an interplanetary flight (to Mars). Part I. Fundamental notions
p. 34-81
Zur Struktur der schwach ordnungminimalen Kontinuen
p. 82-103
Verteilungsgleiche Zufallsvariablen
p. 104-113