Parak, N., Lippusch, M., Naylor, C., Steyskall, A., Joubert, I.A., Himly, M. and Geppert, M. 2020. Gold and Silver - but safe?. Open Schools Journal for Open Science. 3, 2 (Mar. 2020). DOI:https://doi.org/10.12681/osj.22597.