Harmonic Pattern trading is a great tool used by many price action and price pattern traders around the globe. It is not bullet proof but if it is used wisely, then it can yield enough edge to pull the profits from the market. However, its theory and practice are widely varying from a trader to trader. Here is the scientific guide on harmonic pattern trading. You will find it very useful.
Book Title: Guide to Precision Harmonic Pattern Trading
Book Subtitle: Mastering Turning Point Strategy for Financial Trading