BibTeX

@ARTICLE{iumj11015,
    author = "J. Ahlberg and E. Nilson and J. Walsh",
     title = "Best Approximation Properties of the Spline Fit",
   journal = "Indiana Univ. Math. J.",
  fjournal = "Indiana University Mathematics Journal",
    volume = 11,
      year = 1962,
     issue = 2,
     pages = "225--234",
      issn = "0022-2518",
     coden = "IUMJAB",
   mrclass = "",
}

amsrefs

\bib{iumj11015}{article}{
     author = {Ahlberg, J.},
     author = {Nilson, E.},
     author = {Walsh, J.},
      title = {Best Approximation Properties of the Spline Fit},
    journal = {Indiana Univ. Math. J.},
     volume = {11},
       year = {1962},
     number = {2},
      pages = {225 \ndash 234},
}