After a book with a face on the cover (called Biography), I designed a book with a Maltese Cross on the cover (aptly called Bible). This model’s design is based on my Long Story Short book model. Note that all the pleats radiating from the tessellation molecule are hidden,
so both the back cover and the pages are free of any unnecessary creases.
You can find folding instructions for a book with a plain cover (Long Story Short) at origamiusa.org/thefold/article/diagrams-long-story-short