Peter Neumann had a good number of students several of whom had many many more.<p><a href="https://en.wikipedia.org/wiki/Peter_M._Neumann" rel="nofollow">https://en.wikipedia.org/wiki/Peter_M._Neumann</a><p><a href="https://www.mathgenealogy.org/id.php?id=28732" rel="nofollow">https://www.mathgenealogy.org/id.php?id=28732</a>