What is your opinion of the book "Encyclopedia of the Relics of the Companions" by Sayed Kasravi Hassan?

The encyclopedia "Athar al-Sahaba" by Sayyid Kasrawi Hassan is a scholarly encyclopedia that compiles the narrations (athār) from the Companions (Sahaba) into a single collection, to facilitate the acquisition of knowledge for students. It appears that most of its content focuses on the narrations of the Four Caliphs, and it includes 9195 narrations from 509 Companions, arranged according to the musnads of the Companions and a lexical order of the narrations.