Not exactly what you're looking for, but there are accessible papers listed at http://cba.mit.edu/docs/papers/index.html http://cba.mit.edu/docs/papers/index.ht

Not exactly what you're looking for, but there are accessible papers listed at http://cba.mit.edu/docs/papers/index.html http://cba.mit.edu/docs/papers/index.html Three of the listed papers have Cheung as an author/co-author, the first two look relevant to his conceptual and research progression.