SOME ASPECTS OF STRUCTURE AND LATTICE DYNAMICS OF TOURMALINS AND BORACITES STUDIED BY MÖSSBAUER EFFECT I.S. ZHELUDEV, V.F. BELOV, V.G. PILNEV and A.F. BELOV J. Phys. Colloques, 35 C6 (1974) C6-633 DOI: 10.1051/jphyscol:19746140