[Clipart] [Open Clip Art Library] Legal use of clip art

[noreply at openclipart.org]

Hi! First let me thank you for sharing these wonderful creations.

I just want to know if it's legal to use some of the artwork submitted here to use for tshirt design that i'll be selling for my site? Are there any restrictions? The creator and openclipart.org link will be created on each page where the clipart will appear. 

Thanks!