Hello! I don’t think I’ve uploaded many user icons here on DW, mostly they imported iirc from my LJ a few years ago. Looking at my icons, it looks like I placed the maker’s username in the comments field of the icon. But really, you’re welcome to credit how you prefer and is consistent with what you’ve done for other icons; I’m not trolling anyone’s userpics to enforce one style of credit. I appreciate the credit and am happy with that. I’m glad you found some icons that you like!