So, Fox111 suggested a book in the Planning for a Large Event thread
I think this sub-forum could be a great place to list books that you've found useful for any level of play for airsoft. Ideally, a link to a review of the book in the review section would be helpful. Even posting books that you've bought and turned out not to be so good would be helpful for people to avoid spending money on a subpar resource.
The post should have the full name of the book and the authors, a link to Amazon or Chapters would be appriciated, ISBN or ISSN numbers for extra points. Even just a sentence or two review if you don't want to post a full review in the review section would be still helpful for people to decide.