  This is a revised version of ANT-0045.
  If K is a number field of degree n with discriminant D, if K=Q(a) then
H(a)>c(n)|D|^(1/(2n-2)) where H(a) is the height of the minimal polynomial of
a. We ask if one can always find a generator a of K such that
d(n)|D|^(1/(2n-2))>H(a) holds. The answer is yes for real quadratic fields.
