TY - JOUR A1 - Hellwig, Angelika A1 - Volkmann, Lutz T1 - Sufficient conditions for λ′-optimality in graphs of diameter 2 JF - Discrete mathematics Y1 - 2004 SN - 1872-681X (E-Journal); 0012-365X (Print) VL - Vol. 283 IS - Iss. 1-3 SP - 113 EP - 120 ER -