Dennis Grimwood – OESTEX —-> Screen-Grids
Amp Books Tutorials – ampbooks.com
Designing Valve Preamps for Guitar and Bass, Second Edition
Designing Power Supplies for Valve Amplifiers, Second Edition
Dave Funk’s Tube Amp Workbook: Complete Guide to Vintage Tube Amplifiers Volume 1 – Fender
Radiotron Designer’s Handbook, 3rd Edition – In-line below
Class A Exposed and Explained by Randall Smith – What is Class A and how does it differ from Class AB? – In-line below