The electrical resistance R in a superconducting Ba1-xKxBiO3 single cr
ystal is studied as a function of the temperature T and the current I.
The measurements performed without applied magnetic field indicate th
at the flux lines are generated by the self-field and that several tra
nsitions contribute independently to the R(T) and R(I) characteristics
. A phenomenological expression of the R(T, I) dependence is proposed.