Functional Analysis By Frigyes Riesz & Bela Sz.-Nagy (Hardcover, 1955)
You will find that this textbook is written in a conversational, easy-to-follow tone.
Sociology The Basics by Marjorie E. Donovan (English) Paperback Book
A nice touch in this textbook is the space provided for writing your own notes.
Introduction to Quantum Mechanics by Pauling / Wilson 1935 Vintage HC (11119RK)
This textbook is the same edition used in my friend’s class last year.