Comparison of the viewpoints on track treeing in foil CR-39

There have been three main approaches to the understanding of the formation of tree tracks in CR-39 foils during electrochemical etching: ''Breakdown in Divergent Field'' ''Internal Heating Effect'' and ''Electrostriction-Vibration-Fatigue-Etching-Fracture''. Both ''BDF'' and ''IHE'' have failed to explain not only the etching parameters effects but also phenomena observed in experiments. The ''EVFEF'' model gives agreement with all experiments so far. (author)