Yeah. Whenever I had trouble with a topic, it was because my core knowledge was weak and rusty. I was in Instrumentation and Control. The stuff in Control Theor

Yeah. Whenever I had trouble with a topic, it was because my core knowledge was weak and rusty. I was in Instrumentation and Control. The stuff in Control Theory was all Pontryagin, Lyapunov, Bellman, Evans, etc. We were fortunate enough to have a very good Professor who taught a course that is state of the art (continuous control in 3rd year, and discrete control systems in 4th year. Optimal control and RST controllers). For applying the stuff, it's sort of easy. But I know that I'll never appreciate the beauty of it until I understand the concept of stability from a "Calculus" stand point and how it relates to systems. Anyhow, I'm also acquiring Russian. Many Russian books have been translated but a lot have not.