  The electron-phonon interaction (EPI) in transition metal diborides TB_2
(T=Zr, Nb, Ta) is investigated by point-contact (PC) spectroscopy. The PC EPI
functions were recovered and the EPI parameters lambda<0.1 were estimated for
all three compounds. Common and distinctive features between the EPI functions
for those diborides are discussed also in connection with the superconductivity
in MgB_2.
