Good books about activemq/network of brokers

[Enrico Olivelli]

Hi,
I'm looking for something like ActiveMQ in action, but covering the most 
recent features of AMQ
I'm currently using AMQ 5.8 and I would like to upgrade to 5.9
I'm going to extend my simple master-slave (2 brokers) setup to a more 
complex network of brokers, because the load in my application is 
increasing and I need a more scalable system

Any suggestion ?

thanks
Enrico