  In this note we show that if f belongs to Hp(Rn)\capLs(Rn), where 0 < p <= 1
< s < 1, then there exists a (p;infinite)-atomic decomposition which converges
to f in Ls(Rn). From this fact, we prove that a bounded operator T on Ls(Rn)
can be extended to a bounded operator from Hp(Rn) into Lp(Rn) if and only if T
is bounded uniformly in Lp norm on all (p;infinite)-atoms. A similar result is
also obtained from Hp(Rn) into Hp(Rn).
