A friend was excited to discover a printed reference in a 1930s publication to her ancestor that contained the year and place of his birth in Germany in the early 18th century.
I had to tell her that she was just getting started. A printed reference nearly 200 years after they fact may be correct, may be wrong, or somewhere in between. Best to use the reference as a clue to further research and not just to assume it is correct.
It may also be helpful to see if the book lists any sources as to where the information contained in the book was located.