@book{
international1990iaea,
title={The Use of Gamma Ray Data to Define the Natural Radiation Environment},
series={TECDOC Series},
number={566},
year={1990},
url={http://www.dgdingfa.net/publications/822/the-use-of-gamma-ray-data-to-define-the-natural-radiation-environment},
publisher={INTERNATIONAL ATOMIC ENERGY AGENCY},
address={Vienna}
}