Gary Bencivenga's Marketing Maxims
“Copywriting” is a misnomer. “Copyresearching” is more accurate.
Eddie Shleyner • Very Good Copy: 207 Micro-Lessons on Thinking and Writing Like a Copywriter
Scientific Advertising (1923): 1923 Library of Congress Facsimile Edition
amazon.com
Research Like an Obsessed Detective Before You Write a Word