@book{467915,
  address    = {[Lima]},
  pages      = {76},
  publisher  = {Ministerio de Educación},
  title      = {Cálculo 4},
  url        = {http://www.sil.org/americas/peru/show_work.asp?id=20653},
  year       = {1972},
  country    = {Peru [PE]},
  lgcode     = {Amarakaeri [amr]},
  macro_area = {South America},
  sil_id     = {20653},
  src        = {sil16},
  subject    = {Arithmetic [Zarth]}
}