@book{
      international1991iaea,
      title={X-ray and Gamma-ray Standards for Detector Calibration},
      author={ },
      series={entity},
      number={619 },
      year={1991},
      isbn={ },
      url={/publications/875/x-ray-and-gamma-ray-standards-for-detector-calibration },
      publisher={INTERNATIONAL ATOMIC ENERGY AGENCY },
      address={Vienna}
    }