Been using this for decades; my first boss, a PhD physicist, out of college got me started on using this. It's still being sold today: https://www.amazon.com/Na

Been using this for decades; my first boss, a PhD physicist, out of college got me started on using this. It's still being sold today: https://www.amazon.com/National-Computation-Notebook-Inches-43648/dp/B00007LV4B https://www.amazon.com/National-Computation-Notebook-Inches-...