You will find sketchy websites offering a PDF. These are almost always unauthorised scans. I recommend avoiding them – the scan quality is often poor (crooked pages, missing plates), and copyright status is unclear for post‑1970s editions. A cheap used physical copy is vastly better for actual drawing practice.
Before 3D printers and CAD renders, we had isometric drawing. This section teaches you how to create a 3D illusion using 30-degree angles. Green’s exercises are famous for transitioning students from flat shapes to volumetric forms. technical drawing by jn green pdf
If you want a digital copy, consider these legal avenues: You will find sketchy websites offering a PDF