I purchased this book because I thought it'll be an update of the author's
classic 'Microwave Scanning Antenna' containing new material as well. During my review of the book and identifying a lot of flaw equations, I started deriving them myself or grabbed the corresponding papers which were referenced. So to recap the lessons learnt so far, I would recommend not to solely rely on this book but be cautious (especially when using the equations) and use the reference list and/or stick to the old 'Microwave Scanning Antennas' released in the 60s.