@incollection{compref49,
   author = {Bennett,CH},
   year = {1990},
   title = {How to Define Complexity in Physics, and Why},
   booktitle = {Complexity, Entropy and the Physics of Information},
   editor = {Zurek,WH},
   publisher = {Addison-Wesley},
   address = {Redwood City California},
   pages = {137-148}
}