@misc{prange_quality_control_1990, 
author={Prange, A., Kramer, K., Reus, U.},
title={Quality control of ultra-pure reagents: a challenge for TXRF},
year={1990},
howpublished = {conference lecture: Vienna (A);},
note = {Prange, A.; Kramer, K.; Reus, U.: Quality control of ultra-pure reagents: a challenge for TXRF. 3rd TXRF-Workshop. Vienna (A), 1990.}}