What paper notebook dimensions are considered to be standard?
A6 size Smart Reusable Erasable Notebook Microwave Wave Cloud Erase Notepad Note Pad Lined With Pen save paper - AliExpress
WIRE A6 LINED SPIRAL NOTEBOOK - Whitelines
Understanding Common Paper Sizes - The Goulet Pen Company
Amazon.com : A6 Size Simple Lined Note Paper Planner Insert, Sized and Punched for 6-ring Notebooks (4.1" x 5.8”). THIS IS A EUROPEAN STANDARD A6 SIZE. YOUR A6 MAY BE DIFFERENT. PLEASE
Notebook Sizes: The Ultimate FAQ Guide - Honeyoungbook