It is indeed a great place to start. First of all, it is a scholarly book, published by the University of Georgia Press. The authors, Frank O. Mora and Jerry W. Cooney, are both published scholars within the field of Paraguayan and American history. Like a good scholarly book, it has extensive sources, reflecting its wide use of source material in Spanish and English. The reviews of the book published in academic journals all consider it a great overview of an underexplored topic.

All in all, you can not go wrong with this particular book.