Let
denote a positve rational polyhedrial cone and
a facet of the cone. Let
-
be a linear form, such that its kernel contains the facet. Suppose that the linear form is given by integers which are coprime. Show that
![{\displaystyle {}\ell }](https://wikimedia.org/api/rest_v1/media/math/render/svg/e9cf8d22680450b2e9b870da28e083a971ad21ce)
or
![{\displaystyle {}-\ell }](https://wikimedia.org/api/rest_v1/media/math/render/svg/5f933673fc95407f2cb52759a9b65443273813bc)
is the canonical integral linear form of
![{\displaystyle {}F}](https://wikimedia.org/api/rest_v1/media/math/render/svg/93572d890f704d0126d032045604fd170e0fba8f)
.