摘要
D. Edmunds and R. Edmunds have obtained the following result (cf. Can. J. Math.,38(1986), 5: 1181--1191): Let Ω be a bounded, non-empty open subset of R<sup>n</sup>,(?)Ω∈C<sup>∞</sup>,ψ,(t)=e<sup>?</sup>-1, (V∈(1, +∞)) and k∈N. If f ∈ W<sup>k</sup>E<sub>ψ</sub>(Ω), f/d<sup>k</sup> ∈L<sub>ψ</sub>(Ω), then f∈W<sub>O</sub><sup>k</sup> E<sub>ψ</sub>(Ω).