ABSTRACT
DEFINITION 5 . 2 . 1 . We shal l denote by VLq, 1 < q < oo, the set of a l l smoo th functions (p such that daip G Lq(Rn) for a G N n . Suppose that (p
e VLq, e > 0. W e say that the ipe converge to ip i n V^q i f the ^ a ^ e tend to daip as e —> 0 i n L q ( R n ) for a l l a G N n .
