Let K be a field and let G be a finite group. G is K-admissible if the
re exists a Galois extension L of K with G = Gal(L/K) such that L is a
maximal subfield of a central K-division algebra. This paper contains
a characterization of those number fields which are Q(16)-admissible.
This is the same class of number fields which are 2A(6) = SL(2, 9) an
d 2A(7) admissible.