@misc{wille_isotopic_abundance_1990, 
author={Wille, P., Jede, R.},
title={Isotopic abundance in natural iron},
year={1990},
howpublished = {conference lecture: Strasbourg (F);},
note = {Wille, P.; Jede, R.: Isotopic abundance in natural iron. In: Proceedings of the 7th ASTM-EURATOM Symposium. Strasbourg (F). 1990. 403ff.}}