Ask HN: Seeking Book

Hello All,

Many years ago I came across a book from a female Researcher which was basically using low-level mathematics to model low-level type 'circuits' or 'functions'. Not circuits in the electrical sense but I do know this researcher eventually did work for some Intelligence Agencies as part of extensions to her work. Problem I have is I have searched high and low via various search engines though with proliferation of AI texts it has increased the noise level. If anyone is familiar with this book it would be much appreciated.