13F99 Bezout ring 3 elementary divisor ring 2 neat ring 2 06F20 1 Hermite ring 1 clean ring 1 clear ring 1 diagonal reduction of matrices 1 duo ring 1 elementary reduction of matrices 1 neat range one 1 regular ring 1 ring with elementary reduction of matrices 1 rings of almost stable range 1 1 semiexchange ring 1 semihereditary ring 1 stable range 1 stable range 1 1 stable range one 1