=== «Dragon Quest IX» === The book is remplaced by the Defeated Monster List in the Battle Records menu (availiable after you encountered Stella). (dragon-quest.org)
Monster Hunter World Monster List: strengths, weaknesses, carves and rewards for all monsters in the game (vg247.com)
It is revealed when you check Greygnarl's spot in the Defeated Monsters List after you defeat Greygnarl in his grotto that he and Barbarus are brothers. (dragon-quest.org)