Jens-P. Bode Hans-Dietrich O. F. Gronau Heiko Harborth Some Ramsey Schur Numbers. 25-30 2005 14 Combinatorics, Probability & Computing 1-2 http://dx.doi.org/10.1017/S0963548304006595 db/journals/cpc/cpc14.html#BodeGH05