I am preparing a lecture course on the applications of operator theory where I intended to make some numerical analysis application. I was wondering about this question while browsing the literature I can access. [Lax and Richtmyer][1] (1955) start with a vague reference to [Courant, Friedrichs, and Lewy][2] (1928). [Trotter][3] (1958) on the other hand refers to von Neumann, without any specific reference. Since I have no deeper background in numerical analysis, I might be missing some obvious point. So can someone tell me (with a reference) who introduced the notion of stability in numerical analysis? [1]: http://www.mathe.tu-freiberg.de/~ernst/Lehre/IVP/Literatur/laxRichtmyer1956.pdf [2]: http://www.digizeitschriften.de/dms/img/?PPN=GDZPPN002272636 [3]: http://projecteuclid.org/euclid.pjm/1103039709