I read that in Robert Shelton's great bio of Bob titled NO DIRECTION HOME.
Actually what is written in Shelton's book is that when he was a child or teenager the only comics Bob read were Illustrated Classics. That is the same as Classics Illustrated.
I am sure he also read many full length novels.
But many high school kids back then used Classics Illustrated to make their book reports.
Fastest way to the Nobel Prize for Literature.