Comments are given on the application of the Bogoliubov-Tyablikov appr
oach to the bipolaron problem in a recent paper by Lakhno [Phys. Rev.
B 51, 3512 (1995)]. This author believes that his model (1) is the tra
nslation-invariant adiabatic theory of bipolarons and (2) gives asympt
otically exact solutions in the adiabatic limit while the other approa
ches are considered as either phenomenological or variational in natur
e. Numerical results by Lakhno are in contradiction with all other pap
ers published on the subject because his model leads to much lower ene
rgies. Thus, the author concludes that bipolarons ''are more stable th
an was considered before.'' We prove that both the analytical and the
numerical results presented by Lakhno are wrong.