Books are stored in the Catalog, so you would have the best success by exporting your book as a catalog, including all the images, and moving that to the other computer.
One the first computer:
1. Go to the Book in the Collections panel
2. Right click and choose "Export this Collection as a Catalog..." (Exporter cette collection comme un catalogue)
3. Make sure you select the option to "Export Negative Files."
4. Copy the result to a portable media
Then on the second computer:
1. Attach the portable media with your new catalog from above.
2. File > Import From Another Catalog...
3. Choose the catalog file you created above
Now you should have the images, collection and book moved to the new computer.
Thank's for your tip.It works perfectly!
Have a nice day.