The possibility of a phase transition from the one-gap superfluid stat
e with the singlet or triplet pairing of fermions to the two-gap super
fluid state corresponding to the superposition of states with the sing
let and triplet pairing in a Fermi liquid is considered. The thermodyn
amic stability of new two-gap solutions is analyzed. (C) 1998 American
Institute of Physics. [S1063-777X(98)01201-8].