Mapping of physiological and trace elements with X-PEEM B.H. Frazer, B.R. Sonderegger, B. Gilbert, K.L. Richter, C. Salt, L.M. Wiese, D. Rajesh, S.P. Howard, J.F. Fowler, M.P. Mehta and G. De Stasio J. Phys. IV France, 104 (2003) 349-352 DOI: 10.1051/jp4:200300097