An e-Reader such as FBReader http://www.fbreader.org/ is needed to read this book.
I have been a fan of Traveller, Striker and Squad Leader over the years. Traveller (and its miniature rules counterpart, Striker) both have vehicle design systems spanning many decades of technology development.
Hence the actual historical development of armament design is of great interest. This little booklet, nicely laid out in ePub format, traces the need for an anti-aircraft weapon and how it was built on the chassis of existing tanks.
The tension between cost, time and suitability of the weapon to its purpose all play out in this book. I won't "spoil the story" - download and read it if you want to know!
Great backgrounder for a tank / weapons designer. I am thinking of using the specifications for a design for MegaTraveller, and this will provide pictures for the weapon. So it provides for inserting into a role play game.
Even without a design system in your war game or role play game, the detailed specifications given here will make it easy to approximate if needed.