@article{Buch2007,
  author    = {Christian Leopold von Buch},
  title     = {{\"U}ber Ceratiten},
  journal   = {Abhandlungen der K{\"o}niglichen Akademie der Wissenschaften in Berlin, Phys. Kl.},
  volume    = {1848},
  pages     = {1 -- 30c},
  year      = {2007},
}