Using the example of an Austrian engineer and mathematician, Richard von Mises, the article documents the diversity of the lines of influence of Klein’s spirit on mature “distance learning students,” in particular on those who contributed to Klein’s Encyklopädie. Klein also had an indirect effect on von Mises through established mathematicians such as Georg Hamel and Karl Heun, and through his seminar. Although von Mises was unable to attend the latter, he was undoubtedly aware of its content through his contacts in Göttingen and through publications. Later von Mises worked increasingly on numerical and graphical methods in applications. These methods were less represented in Klein’s seminars but were developed by Carl Runge who was strongly supported by Klein. As head of the Berlin Institute for Applied Mathematics in the 1920s, von Mises ultimately regarded himself as the true heir to Klein, which included some sentiment of German-Austrian solidarity after the defeat in the war. New sources in this article are primarily correspondence between von Mises and his mother, with Klein, and with Heun.