BibTeX

@ARTICLE{iumj20107,
    author = "Paul Butzer and U. Westphal",
     title = "The Mean Ergodic Theorem and Saturation",
   journal = "Indiana Univ. Math. J.",
  fjournal = "Indiana University Mathematics Journal",
    volume = 20,
      year = 1971,
     issue = 12,
     pages = "1163--1174",
      issn = "0022-2518",
     coden = "IUMJAB",
   mrclass = "",
}

amsrefs

\bib{iumj20107}{article}{
     author = {Butzer, Paul},
     author = {Westphal, U.},
      title = {The Mean Ergodic Theorem and Saturation},
    journal = {Indiana Univ. Math. J.},
     volume = {20},
       year = {1971},
     number = {12},
      pages = {1163 \ndash 1174},
}