Small positive values of indefinite ternary forms

For an indefinite quadratic form f(x(1),...,x(n)) of discriminant d, let P(f) denote the greatest lower bound of the positive values assumed by f for integers x(1),..,x(n). This paper investigates the values of P-3/\d\ for nonzero ternary forms of signature -1, and finds the only remaining class of forms with P-3/\d\ > 1/2.