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 **Lectures & Courses**
 - [Khan Academy](https://www.khanacademy.org/)
 - [MIT OpenCourseWare: Linear Algebra](https://ocw.mit.edu/courses/18-06sc-linear-algebra-fall-2011/)
+- [Introduction to Higher Mathematics](https://www.whitman.edu/mathematics/higher_math_online/) (free online course)
 - [Start Learning Mathematics (playlist)](https://www.youtube.com/playlist?list=PLBh2i93oe2qtbygdXz4u6Mkh7c_hMLBA8)
 
 **Books & Textbooks**