BibTeX

@ARTICLE{iumj12014,
    author = "Avner Friedman and Walter Littman",
     title = "Partially Characteristic Boundary Problems for Hyperbolic Equations",
   journal = "Indiana Univ. Math. J.",
  fjournal = "Indiana University Mathematics Journal",
    volume = 12,
      year = 1963,
     issue = 2,
     pages = "213--224",
      issn = "0022-2518",
     coden = "IUMJAB",
   mrclass = "",
}

amsrefs

\bib{iumj12014}{article}{
     author = {Friedman, Avner},
     author = {Littman, Walter},
      title = {Partially Characteristic Boundary Problems for Hyperbolic Equations},
    journal = {Indiana Univ. Math. J.},
     volume = {12},
       year = {1963},
     number = {2},
      pages = {213 \ndash 224},
}