Although I would like to offer everything on this website under a Creative Commons License, I have found hard worked materials from my website on sites like CourseHero. While I want my materials to help students learn, sites like Chegg, CourseHero, and the like typically do not promote real learning, and worse yet often promote cheating/plagiarism. Moreover, these sites charge, which I am also against. Compare these sites to much better websites like Khan Academy.
Therefore, I retain the copyright to all the materials I have created on this website. However, if you want to link to these resources feel free! If you would like to post these on your own sites, send me an email and ask! Most likely if you are not a site like the ones above, I will be very amenable to having you distribute the materials! While I try to use only my own materials, there are cases where I have found other material I found useful for students. When possible, I obtain permission to use these resources. However, if you find material of yours that I have used that you would like removed or cited, please, let me know.