@book{
international2010iaea,
title={Worldwide Open Proficiency Test: Determination of Naturally Occurring Radionuclides in Phosphogypsum and Water},
series={Analytical Quality in Nuclear Applications Series},
number={18},
year={2010},
url={http://www.dgdingfa.net/publications/8480/worldwide-open-proficiency-test-determination-of-naturally-occurring-radionuclides-in-phosphogypsum-and-water},
publisher={INTERNATIONAL ATOMIC ENERGY AGENCY},
address={Vienna}
}