MICROSTRUCTURE AND COERCIVITY IN (Nd, Dy)-(Fe, Co)-B BASED SINTERED PERMANENT MAGNETS WITH MINOR Nb AND Ga ADDITIONS G. F. Zhou, X. K. Sun, Y. C. Chuang, L. Gao, Z. Yu, C. L. Xiao and W. Liu J. Phys. Colloques, 49 C8 (1988) C8-573-C8-574 DOI: 10.1051/jphyscol:19888260