@book{koentjaraningrat1961,
  address = {Ithaca},
  author  = {Koentjaraningrat, R. M.},
  key     = {Koentjaraningrat (1961)},
  title   = {Some Social Anthropological Observations on Gotong Rojong Practices in Two Villages of Central Java},
  year    = {1961}
}