MÖSSBAUER STUDIES OF THE ONE-DIMENSIONAL ANTIFERROMAGNETIC SYSTEMS : A2FeF5 G.P. Gupta, D.P.E. Dickson and C.E. Johnson J. Phys. Colloques, 40 C2 (1979) C2-304-C2-306 DOI: 10.1051/jphyscol:19792107