I am writing a book which compares over one-hundred vendors. My question is:
a) Can I legally put all their logos on the front and back page as the cover?
b) Inside the book I am speaking about each product (I am not comparing and contrasting – simply speaking out each one). Can I include logos there legally?

When you answer please but a) – b) and if possible a link to back it up.
This book will be sold for profit and I am very concerned about the usage of logos. I have been informed that I need to include a disclaimer that my book is not affiliated with or sponsored by ABC OR XXX company.

Thanks for your feedback.
internet marketing