''Intelligent life in the Universe '' the book - anyone has read this?

A few months ago, I acquired a big box of book from the 70's. Among them, sci-fi novels in english (a rare thing in Quebec city). It was from authors such as Asimov, Clarke, Dick, Farmer and many others. There's many treasures in that box, many hours of reading material.

Among the box I found a book written by Carl Sagan and I.S. Shklovskii titled ''Intelligent life in the Universe ''. Published in 1966, it is a very dense 509 pages book. Looks like serious research, with numerous diagrams, charts and graphs. It is separated in three chapters : the universe, life in the universe and intelligent life in the universe.

I began reading the introduction this evening but this will be at least a few weeks before I finish this. Does anyone here have read this book ? Look like serious research done by serious scientist. I will probably post my comments as I read this.

About the authors:
en.wikipedia.org...

en.wikipedia.org...

Salute