Nayden Kostov figure dans ce catalogue avec 9 livres, dont "1123 Hard to Believe Facts", "463 Hard to Believe Facts: Better Explained, Counterintuitive and Fun Trivia" et "523 Hard to Believe Facts".
1123 Hard to Believe Facts
2016
Which is NOT True?: The Quiz Book
2016
Fascinating Facts for the Whole Family: Trivia about Human Body and Cute Animals
2017
853 Hard to Believe Facts
2018
523 Hard to Believe Facts
2019
323 Disturbing Facts about Our World: Shocking, Ironic or Simply Sad Pieces of Trivia
2020
463 Hard to Believe Facts: Better Explained, Counterintuitive and Fun Trivia
2021
A Question a Day Keeps the Boredom Away
2022
373 Mind-Boggling Facts and Questions from the Puzzle Vault
2024