I'm planning my next trip to Canada (in July) and I'm wondering if there is a good guidebook on parks in Alberta (mainly Banff and Jasper). The book should have a review of the trails and suggestions about how to organize a visit there.

I believe there are tons of books but I'd like have your suggestions. Moreover the book should be available for on-line shop (i.e. on Amazon) since I live in Italy.

Thank in advance, Marco in Milan, Italy