Saved by Eden M. B. Roman and
Earthing: The Most Important Health Discovery Ever! (Second Edition)
PEMF - The Fifth Element of Health: Learn Why Pulsed Electromagnetic Field (PEMF) Therapy Supercharges Your Health Like Nothing Else!
amazon.com

And for a deep dive into the science and best practices for grounding and earthing, I highly recommend the book Earthing, by Clint Ober, Stephen T. Sinatra, and Martin Zucker.