Add Cover

[Whoof]

There's no English cover for Max Wertheimer's "Productive Thinking."

https://www.goodreads.com/book/show/4...

The only cover I could find was for a paperback edition on amazon:

http://www.amazon.com/gp/product/0422...

But I figured having one english cover is better than not having any.

[Z-squared]

Hi Whoof,

We always keep covers edition-specific. However, the paperback cover you pulled from Amazon was not on Goodreads either, so I added it to the paperback edition here:

https://www.goodreads.com/book/show/5...