via Never. Hong Se-young (October 20, 2021). "[단독] 윤도현 '싱어게인2' 합류, 제2의 이승윤·정홍일·이무진 발굴" [[Exclusive] Yoon Do-hyun joins 'Singer Gain 2', discovers the second
Archived from the original on April 12, 2023. Retrieved February 12, 2024. 정홍일 #그늘 / Music Video, archived from the original on May 26, 2024, retrieved
Retrieved July 7, 2021 – via Naver. Kim, Kyung-mi (April 5, 2021). "이승윤X정홍일X이무진 '유명가수전 히든트랙' 9일 티빙서 공개". Newsen (in Korean). Archived from the original
Aired 1 12 16 November 2020 15 February 2021 Lee Seung-yoon 이승윤 Jeong Hongil 정홍일 Lee Mu-jin 이무진 2 12 6 December 2021 28 February 2022 Kim Ki-tae 김기태 Kim So-yeon