Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Good source about this subject

I read this book, translated to the portuguese, here in Brazil.Good source about general military history.This books talks about military history, since stone age war, until almost our times.With no prejudices, and almost unbiased, this book is good.The problems in this book are small.There's some thing in it who are outdated, and this book sometimes calls too much about minor subjects.After all, this book is good and easy to read.