Dear Heinz,
these mathematicians were Jakob Rosanes (1842-1922) and Rudolf
Sturm (1841-1919).
Regards, Julio GC
PS If you are fond of chess I'm sending you a couple of Rosanes's most
notorious games:
Rosanes, J - Anderssen, A (Breslau, 1862)
1.e4 e5 2.f4 d5 3.exd5 e4 4.Bb5 c6 5.dxc6 Nxc6 6.Nc3 Nf6 7.Qe2 Bc5
8.Nxe4 O-O 9.Bxc6 bxc6 10.d3 Re8 11.Bd2 Nxe4 12.dxe4 Bf5 13.e5 Qb6
14.O-O-O Bd4 15.c3 Rab8 16.b3 Red8 17.Nf3 Qxb3!! 18.axb3 Rxb3 19.Be1
Be3 (O-1)
Rosanes, J - Anderssen, A (Breslau, 1863)
1. e4 e5 2. f4 exf4 3. Nf3 g5 4. h4 g4 5. Ne5 Nf6 6. Bc4 d5 7. exd5 Bd6
8. d4 Nh5 9. Bb5 c6 10. dxc6 bxc6 11. Nxc6 Nxc6 12. Bxc6 Kf8! 13. Bxa8
Ng3 14. Rh2 Bf5 15. Bd5 Kg7 16. Nc3 Re8 17. Kf2 Qb6 18. Na4 Qa6 19. Nc3
Be5 20. a4 Qf1!! 21. Qxf1 Bxd4 22. Be3 Rxe3 23. Kg1 Re1 (0-1)