Why the book is interesting today is that it still is important and the most authoritative work on how to value financial assets. (businessinsider.com)
«Kennilworthy Whisp's Quidditch Through the Ages is the most authoritative work on Quidditch in the wizarding world,» said Pottermore Digital Audio Product Manager Ravina Bajwa. (goodereader.com)
See for instance the following authoritative work: (redeeminggod.com)