I am looking for reference to the following imbedding theorem

Theorem

For any $s>1/2$ fractional Sobolev space $W^{s}_2(0,1)$ imbeds compactly into $C([0,1])$.

I know how to prove it but I need the reference for my article.

Thanks.

I am looking for reference to the following imbedding theorem:

Theorem

For any $s>1/2$ fractional Sobolev space $W^{s}_2(0,1)$ imbeds compactly into $C([0,1])$.

I know how to prove it but I need the reference for my article.

Thanks.