@book{
  author = "Boulding, Kenneth Ewart, 1910-, Glahe, Fred R., Singell, L. D.",
  title = "Collected papers",
  year: c1971
  key = "Economics--Collected works",
  publisher = "Colorado Associated University Press",
  address = "Boulder",
  ISSN/ISBN = "9780870810114 [0870810111] (v. 1)",
}