I ran across this advertisement for what is now a Hobby Library essential, The American Premium Guide to Baseball Cards by Ron Erbe, in the October 1981 issue of The Trader Speaks.
As the advertisement says, the book is massive, at 752 softbound pages.
It’s full of interesting info. Here’s the Table of Contents.
As an example of the book’s awesomeness, here’s a photo of a 1956 Topps promotional sheet—the same one I shared from Baseball Cards magazine.
They also included a nice collage of T206 white border backs.
But every set has a nice, insightful introduction.
If you have a Hobby Library, I recommend picking up a copy of this book. Despite inflation, you can still get a copy shipped to you for the cover price of $14.95.