A simple tip that changed the way I work when I research a project and have to navigate multiple reference papers: merge them into a single doc.
This way I find it that it’s simpler to search through all papers, rather than switching between windows and doing it paper by paper.
To help with navigating the merged papers I usually generate a Table of Contents based on the merged files. This creates a simple click through TOC at the start of the merged doc.
Another trick to keep the merged document easy to navigate is to wrap the existing bookmarks in a parent (top level) bookmark based on the filename.
I’ve found that if I PDF compress these scans they take up way less space (from 100s to few MBs) and Preview is much snappier when browsing/searching through them.
The compressor for PDF files online: https://www.sejda.com/compress-pdf
In the day and age of the internet you can find a lot of books online. Here’s a few tips on how to find them.
Google is the best search engine for the web. Use it to find what you are looking for.
Here are some tips on how to search Google efficiently.