Sincerely, A mathematician"

I smiled, feeling a connection to the unknown mathematician who had written the note. As I began to flip through the pages of the book, I noticed that certain passages were underlined, and key theorems were annotated with marginal notes. It was as if the previous owner had been studying for a high-stakes exam, and had poured their heart and soul into mastering the material.

"Dear student,

I pulled the book off the shelf, blowing off the thin layer of dust that coated its surface. As I opened it, a piece of paper slipped out, fluttering to the floor. I picked it up, smoothing out the creases to reveal a handwritten note.

The proprietor nodded, and disappeared into the stacks, leaving me to continue my journey through the world of geometry, guided by the trusty pages of Walker and Miller.