Comment on PRB 59, 9195 (1999) and 62, 14061 (2000) by D. S. Golubev and A. D. Zaikin, and on cond-mat/0110495 by D.S. Golubev, A.D. Zaikin, and Gerd Sch\"{o}n

The relation between “non-perturbative analysis” of low temperature dephasing and the perturbation theory is discussed. Contributions missed in each order of the perturbation theory due to “non-perturbative analysis” are listed. Main source of the mistake is pointed out.