H. Kraus, T. Peterreins, F. Probst, F. Vonfeilitzsch, RL. Mossbauer, V. Zacek, E. Umlauf: HIGH-RESOLUTION X-RAY-DETECTION WITH SUPERCONDUCTING TUNNEL-JUNCTIONS. 1986Europhysics Letters: 1. ISBN 0295-5075 http://dx.doi.org/10.1209/0295-5075/1/4/002