MÖSSBAUER SPECTROSCOPIC STUDIES OF MAGNETIC PROPERTIES OF ULTRA-THIN FERROMAGNETIC FILMS S.W. Duncan, R.J. Semper, A.H. Owens and J.C. Walker J. Phys. Colloques, 41 C1 (1980) C1-213-C1-214 DOI: 10.1051/jphyscol:1980167