Which Symmetric Homogeneous Polynomials Can Be Proved Positive Semi-definite by Difference Substitution Method?.

Liangyu Chen Zhenbing Zeng Which Symmetric Homogeneous Polynomials Can Be Proved Positive Semi-definite by Difference Substitution Method?. 57-71 2007 ASCM http://dx.doi.org/10.1007/978-3-540-87827-8_5 conf/ascm/2007 db/conf/ascm/ascm2007.html#ChenZ07