FLUORESCENCE EXCITATION OF ULTRA- SOFT X-RAY EMISSION SPECTRA USING SYNCHROTRON RADIATION K. FESER, J. MÜLLER, G. WIECH et A. FAESSLER J. Phys. Colloques, 32 C4 (1971) C4-331-C4-333 DOI: 10.1051/jphyscol:1971460