License question

[pgum]

Hello, this repository does not have explicit LICENSE file.
I was made into https://github.com/sharu725/online-cv jekyll theme, which has following attribution:

This theme is designed by Xiaoying Riley at 3rd Wave Media. Visit her website for more themes.

I wanted to use that theme, and modified it for my repo, by adding following attribution:

Resume theme made by Xiaoying Riley under CC Attribution 3.0 License

Made into jekyll theme online-cv by sharu725

But upon checking repository I dont see LICENSE file, so I came unsure if I can word it like that, or should I use

Resume theme is designed by a href="http://themes.3rdwavemedia.com" target="_blank" rel="nofollow">Xiaoying Riley, visit her for more themes.

Made into jekyll theme online-cv by sharu725

Please guide me, and also consider adding LICENSE file to the repo.

BR, Piotr