Nor this one: https://authors.library.caltech.edu/43698/1/25YearsAgo.pdf https://authors.library.caltech.edu/43698/1/25YearsAgo.pdf It was the original paper

Nor this one: https://authors.library.caltech.edu/43698/1/25YearsAgo.pdf https://authors.library.caltech.edu/43698/1/25YearsAgo.pdf It was the original paper for this that got me interested in building silicon tools