1. On the nonnegative solution of some system of linear algebraic equations;Faragó;Quaderni del Dip. di Mat., Stat., Inf. and Appl.,1992
2. Positivity of the finite difference scheme for the linear parabolic problem;Faragó;Coll. Math. Soc. J. Bolyai,1991
3. Preserving concavity in initial-boundary value problems;Faragó;Period. Math. Hungar.,1995
4. Nonnegative Matrices in the Mathematical Sciences;Berman,1979
5. On a maximum principle for matrices, and on conservation of monotonicity;Stoyan;Z. Angew. Math. Mech.,1982