I'm a fan of Jeff Danziger, but he crosses a line with his cartoon on the disintegrating Yugo car, July 9, which is equivalent to ethnic stereotyping. The cheap slur comes at a time of agony for Yugoslavians. It would be better to bite US congressmen and federal executives than the already bloodied victims of overseas civil strife.Philip Dacey, Lynd, Minn. Letters are welcome. Only a selection can be published, subject to condensation, and none acknowledged. Please address them to "Readers Write," One Norway St., Boston, MA 02115.