Re: Chess Ratings

On May 9, 12:13=A0pm, samsloan <samhsl...@[EMAIL PROTECTED]
> wrote:
> Elo's book, The Rating of Chess Players, Past and Present, is
> reprinted today.
>
> http://www.amazon.com/dp/0923891277
>
> Professor Elo's book long out of print and almost impossible to obtain
> has just been reprinted, with a foreward by Sam Sloan.

  Is this book already in the public domain? It first appeared in
1978, only 30 years ago. How long do copyrights last for such books?