Dr. Colby Moorberg at Kansas State University presented on an open textbook created for his soil and water conservation course. Students were contributors to the chapters in the book.
(From OpenEd conference - ~24 min YouTube video of session): https://www.youtube.com/watch?v=FDuSZ5tpnsc
Dr. Moorberg published an article on the process and an open textbook.
The textbook is available here.
1.1: Seek out credible resources for a topic.
1.2: Understand the diversity of quality resources available (extension publications, government reports, and other free, credible, online resources).
1.3: Peer-review for comprehension, quality, and consistency.