These are "French notebooks" 20 pages each of paper of a good finish to accept fountain pen ink, heavy enough not to bleed through.
I love the corner illustrations on the blue notebook--the four seasons, with a flowery spring, a beach umbrella, apple picking, and a large, intimidating snowman.
The composition books also have 20 pages each. There are multiplication tables, and linear, circular, volume and other kinds of measuring tables on the back. Amusing, and useful!
The last pair have 160 pages each, of the same quality paper. They are the perfect size to use in my Oberon leather journal covers.
All of these are from Laughing Elephant.