Cumulative sales of "Disease", "What Do You See", "Some Like It Hot", "Hide And Seek", "20 Years After", "The Meaning of Solitude", "Is There Anybody":
Jin Hyang-hee (December 6, 2022). "이적, 청각 장애인 위해 5천만원 기부" [Lee Juck Donation of 50 million won for transfer and hearing impaired] (in Korean). Maeil Business Star Today. Retrieved December 6, 2022 – via Naver.
Hong Se-young (June 21, 2021). "[단독] 이적·성시경→송가인·2PM 우영, '조선탑싱어' 심사위원" [[Exclusive] Jeok Lee, Si-kyung Seong → Ga-in Song, Woo-young of 2PM, judges for ‘Chosun Top Singer]. Naver (in Korean). Sport Donga. Retrieved June 21, 2021.
Hong Se-young (July 20, 2021). "전현무→송가인 '풍류대장' 론칭, 9월 첫방 확정 [공식]" [Jeon Hyun-moo → Song Ga-in ‘Pungryu Captain’ launch, first air confirmed in September [Official]]. Sports Donga (in Korean). Naver. Retrieved July 20, 2021.
Lee Min-ji (October 19, 2021). "오프 더 레코드' 이적-김숙-최유정, 공동 MC 확정(공식)" ['Off the Record' Lee Jeok-Kim Sook-Choi Yoo-jung confirmed as co-MCs (official)] (in Korean). Newsen. Retrieved October 19, 2021 – via Naver.
Park Ah-reum (July 4, 2022). "미스터리 듀엣' 이적 15년만 단독 MC "책임감 무겁지만‥"[공식]" [Mystery Duet' Sole MC after 15 years of transfer "The responsibility is heavy..." [Official]] (in Korean). Newsen. Retrieved July 4, 2022 – via Naver.
Ahn So-yoon (October 18, 2022). "[공식] 정재형x이적x넉살x이미주x안아름, '사내연애' MC 확정..직장 로맨스 리얼리티" [[Official] Jung Jae-hyung x Lee Jeok x Nucksal x Mi-joo Lee x A-reum Ahn confirmed as MC for 'In-house Romance'... Work Romance Reality] (in Korean). Sports Chosun. Retrieved October 18, 2022 – via Naver.
Jo Eun-mi (October 28, 2021). "'2021년 대한민국 대중문화예술상' 오늘(28일) 개최..윤여정, 금관문화훈장 수훈" [‘2021 Republic of Korea Popular Culture and Arts Award’ held today (28th)..Yeojeong Yoon, awarded with the Order of Cultural Merit] (in Korean). Herald POP. Retrieved October 28, 2021 – via Naver.