@misc{146057,
  title      = {Progreso},
  url        = {http://www.sil.org/americas/peru/show_work.asp?id=20577},
  year       = {1967},
  country    = {Peru [PE]},
  lgcode     = {Spanish [spa]},
  macro_area = {Eurasia},
  sil_id     = {20577},
  src        = {sil16},
  subject    = {Science [Zsctx], Teacher's guides [Ztgd]}
}