https://drive.google.com/file/d/1HYX0Drdy71nH2x_nq0Y_H_X9wShnfCGZ/view?usp=sharing
Kwok's notes
https://docs.google.com/document/d/1vGuuilj8i4f0PdAF4fX50DgEk8EPcgRQNMzyIJaaBOU/edit?usp=sharing
