@article{SMJ2_2015_41_4_a6,
     author = {Sekiguchi, Yoshiyuki},
     title = {Notes on {Optimality} {Conditions} {Using} {Newton} {Diagrams} and {Sums} of {Squares}},
     journal = {Serdica Mathematical Journal},
     pages = {431--456},
     publisher = {mathdoc},
     volume = {41},
     number = {4},
     year = {2015},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/SMJ2_2015_41_4_a6/}
}