Johan F.A.K. van Benthem & Patrick Blackburn 
Handbook of Modal Logic [PDF ebook] 

The Handbook of Modal Logic contains 20 articles, which collectively introduce contemporary modal logic, survey current research, and indicate the way in which the field is developing. The articles survey the field from a wide variety of perspectives: the underling theory is explored in depth, modern computational approaches are treated, and six major applications areas of modal logic (in Mathematics, Computer Science, Artificial Intelligence, Linguistics, Game Theory, and Philosophy) are surveyed. The book contains both well-written expository articles, suitable for beginners approaching the subject for the first time, and advanced articles, which will help those already familiar with the field to deepen their expertise. Please visit:http://people.uleth.ca/~woods/Red Series Promo_WP/Pub SLPR.html- Compact modal logic reference- Computational approaches fully discussed- Contemporary applications of modal logic covered in depth