1. On the zeros of a polynomial and of its derivative;de Bruijn;Indag. Math.,1946
2. On the zeros of a polynomial and of its derivative II;de Bruijn;Indag. Math.,1947
3. A conjecture of Schoenberg;de Bruin;J. Inequal. Appl.,1999
4. On a Schoenberg-type conjecture;de Bruin;J. Comput. Appl. Math.,1999
5. On an exposed element of a set of doubly stochastic rectangular matrices;Cihak;Comment. Math. Univ. Carolin.,1970