@article{Bos2013TakkelingB,
   title     = {De Sperwer Accipiter nisus als broedvogel in de provincie Groningen in 2013},
   author    = {Bos, Johan},
   journal   = {De Takkeling},
   volume    = {21},
   number    = {3},
   pages     = {204--208},
   year      = {2013}
}