@article{10_14708_cm_v21i2_5996,
     author = {R. L. Stens and M. Wehrens},
     title = {Legendre transform methods and best algebraic approximation},
     journal = {Commentationes Mathematicae},
     pages = { 351--380},
     publisher = {mathdoc},
     volume = {21},
     number = {2},
     year = {1979},
     doi = {10.14708/cm.v21i2.5996},
     language = {pl},
     url = {http://geodesic.mathdoc.fr/articles/10.14708/cm.v21i2.5996/}
}