Ironía soviética

A.G.Vitushkin, en Mathematical Events of the Twentieth Century, unas memorias colectivas de la matemática rusa del siglo XX:

In the 1970s we seldom traveled abroad. The reasons are known. Here is a typical example. Our colleague, the mathematician Esenin-Vol’pin, had been put in a mental institution for his too emotional response to political events. A letter signed by over a hundred mathematicians was sent to the authorities, insisting on his release, and he was freed. A few years later he emigrated to the USA, whereas those who signed this letter were not permitted to take trips abroad for a long time.

(El libro se puede descargar en PDF desde Google Scholar. Buscando "The Life and Fate of Functional Analysis in the Twentieth Century" (uno de los capítulos) y pinchando en el enlace, te sale todo el libro.)