Still for sale on Amazon (new) and eBay: https://www.amazon.com/How-Entertain-Your-Pocket-Calculator/dp/0917406117 https://www.amazon.com/How-Entertain-Your-Po

Still for sale on Amazon (new) and eBay: https://www.amazon.com/How-Entertain-Your-Pocket-Calculator/dp/0917406117 https://www.amazon.com/How-Entertain-Your-Pocket-Calculator/...