  The goal of this note is to point out an erroneous formula for the
generalised Hessian of the least squares associated with a system of linear
inequalities, that was given in the paper "A finite Newton method for
classification" by O.L. Mangasarian (Optim. Methods Softw. 17: 913--929, 2002)
and reproduced multiple times in other publications. We also provide sufficient
contiditions for the validity of Mangasarian's formula and show that Slater's
condition guarantees that some particular elements from the set defined by
Mangasarian belong to the generalised Hessian of the corresponding function.
