@article{Bos2013TakkelingA,
   title     = {De Sperwer Accipiter nisus als broedvogel in de provincie Groningen in 2012},
   author    = {Bos, Johan},
   journal   = {De Takkeling},
   volume    = {21},
   number    = {2},
   pages     = {129--131},
   year      = {2013}
}