You've assembled and adapted your resources in the way you want to teach them. Now it's time to provide proper attribution to the original authors.
Building on the work of others is awesome. And recognizing those you're building on is a great practice for encouraging sharing of more resources. "Citation" and "Attribution" are often used as synonyms, but they mean two different things. Citation is a scholarly practice for tracking the ideological underpinnings of a work, usually referencing sources like published books, articles, government documents, primary sources, etc. Citation is a norm, not a legal requirement. Attribution is about crediting a copyright holder according to the terms of a copyright license, usually crediting artistic works like music, fiction, video, and photography. Attribution is a legal condition of using a licensed work.
If you are interested in licensing your resulting work, see the challenge on License compatibility (TBD).