Jung Hee-yeon (December 1, 2021). "유지애·김소정→온유·성열 '4분 44초' 캐스팅 [공식]" [Yoo Ji-ae, Kim So-jeong → Onew, Seong-yeol's '4:44' Casting [Official]] (in Korean). Sports Donga. Archived from the original on December 1, 2021. Retrieved December 1, 2021 – via Naver.
Jang Jin-ri (August 2, 2021). "[단독]이성열, 전역 후 연기로 활동 재개...'기억의 시간' 캐스팅" [[Exclusive] Lee Seong-yeol resumes his activities with acting after being discharged from the military... Casting of 'Time to Remember]. Spotify News (in Korean). Naver. Archived from the original on August 2, 2021. Retrieved August 2, 2021.
Jeon Hyo-jin (February 9, 2023). "인피니트 이성열, '넘버스' 출연...김명수와 호흡" (in Korean). Sports DongA. Archived from the original on April 3, 2023. Retrieved February 20, 2023 – via Naver.
Jung, Byung-guen (November 23, 2022). "인피니트 이성열, 데뷔 첫 연극 도전..."설레고 흥분돼" [Infinite Lee Seong-yeol's first play challenge... "I'm thrilled and excited]. The Fact (in Korean). Archived from the original on December 10, 2022. Retrieved December 10, 2022 – via Naver.
Jung Hee-yeon (December 1, 2021). "유지애·김소정→온유·성열 '4분 44초' 캐스팅 [공식]" [Yoo Ji-ae, Kim So-jeong → Onew, Seong-yeol's '4:44' Casting [Official]] (in Korean). Sports Donga. Archived from the original on December 1, 2021. Retrieved December 1, 2021 – via Naver.
Jang Jin-ri (August 2, 2021). "[단독]이성열, 전역 후 연기로 활동 재개...'기억의 시간' 캐스팅" [[Exclusive] Lee Seong-yeol resumes his activities with acting after being discharged from the military... Casting of 'Time to Remember]. Spotify News (in Korean). Naver. Archived from the original on August 2, 2021. Retrieved August 2, 2021.
Jeon Hyo-jin (February 9, 2023). "인피니트 이성열, '넘버스' 출연...김명수와 호흡" (in Korean). Sports DongA. Archived from the original on April 3, 2023. Retrieved February 20, 2023 – via Naver.
Jung, Byung-guen (November 23, 2022). "인피니트 이성열, 데뷔 첫 연극 도전..."설레고 흥분돼" [Infinite Lee Seong-yeol's first play challenge... "I'm thrilled and excited]. The Fact (in Korean). Archived from the original on December 10, 2022. Retrieved December 10, 2022 – via Naver.