  The break-junction tunneling has been systematically investigated in MgB2.
Two types of the break-junction contacts have been exploited on the same
samples, which demonstrated tunnel contact like (SIS) and point contact like
(SnS) behavior. Both of them have shown the existence of the two distinct
energy gaps. We have observed also the peculiarities on the I(V)-
characteristics related to Leggett's collective mode assisted tunneling. -->
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