PaperTotal unimodularity and combinatorial theoremsAlan J. HoffmanLinear Algebra and Its Applications
PaperStaircase transportation problems with superadditive rewards and cumulative capacitiesAlan J. Hoffman, Arthur F. Veinott Jr.Mathematical Programming
PaperInequalities of Rayleigh quotients and bounds on the spectral radius of nonnegative symmetric matricesDon Coppersmith, Alan J. Hoffman, et al.Linear Algebra and Its Applications