Before revision:  We show that (r - g)/2 \left\lfloor {2} }\right\rfloor +1 reflex edge guards are sufficient, where r is the number of reflex edges in a given polyhedron and g is its genus.
After revision:  We show that (r - g)/2 \left\lfloor \frac{r-g{2} }\right\rfloor +1 reflex edge guards are sufficient, where r is the number of reflex edges in a given polyhedron and g is its genus.