@book{ BB24773817,
  author    = "Paju, Jaan",
  title     = "The European Union and social security law",
  publisher = "Hart",
  year      = "2017",
  series    = "Modern studies in European law",
  number    = "v. 77",
  URL       = "https://ci.nii.ac.jp/ncid/BB24773817"
}