@book{
  international1976iaea,
  title={Tracer Studies on Non-protein Nitrogen for Ruminants III},
  series={Panel Proceedings Series},
  year={1976},
  isbn={92-0-111376-5},
  url={https://www.iaea.org/publications/3254/tracer-studies-on-non-protein-nitrogen-for-ruminants-iii},
  publisher={INTERNATIONAL ATOMIC ENERGY AGENCY},
  address={Vienna}
}