BY " PNEUMOCOCCUS IMMUNOGEN (COMBINED)." By MAHENDRA KUMAR BATTACHARYA, Medical Officcr, Bengal Police Hospital, Alipore. The patient, a male, aged 23 years, was first admitted into this hospital on 30th December, 1928, with complaints of dyspepsia and was treated accordingly up to 23rd January, 1929. On 24th January, 1929, he suddenly complained of pain in the risrht side of the chest with ris...

The set packing and set covering models are two useful models in integer programming. Sometimes, due to the special structure of the constraint matrix, the natural linear programming relaxation yields an optimal solution which is integral, thus solving the problem. Perfect, ideal and balanced matrices are three classes of constraint matrices with such integrality properties (for the set packing...