 of the Korea Hapkido Association and Sin Moo Hapkido, and Sung Moo Kwan in Andong)
- Kwon Tae-Man (Hangul: 권태만; First founder of a hapkido dojang in Incheon)
- Kim Yong-Jin (Hangul: 김용진; Founder of the Ulchi Kwan)
- Myung Jae-Nam (Hangul: 명재남; Founder of Hankido and Hankumdo)
- Oh Se-Lim (Hangul: 오세림; former president of Korea Hapkido Federation)
- Myung Kwang-Sik (Hangul: 명광식; Founder of the World Hapkido Federation)
- Kim Moo-Hong (Hangul: 김무홍; Choi's student in 1955, Founder of the Korean Hapkido Association and Shin Moo Kwan in Daegu)
- Moon Jong-Won (Hangul: 문종원; Choi's student in 1955, Founder of Won Moo Kwan in Busan)
- Kim Yoon-Sang (Hangul: 김윤상; Founder of Hapki yusul)
- Yoo Byung-Don (Hangul: 유병돈; Han Kuk Jeong Dong Hapkido, Orthodox Hapkido)
- "합기도 ①" at Doosan EnCyber & EnCyber.com (두산 백과사전) (Korean)
- "합기도 ②" at Doosan EnCyber & EnCyber.com (두산 백과사전) (Korean)
- "합기도 ③" at Doosan EnCyber & EnCyber.com (두산 백과사전) (Korean)
- "합기도 ④" at Doosan EnCyber & EnCyber.com (두산 백과사전) (Korean)
- (Korean) 허인욱의 무인이야기 장보고와 정년 그리고 송징
- Hentz, Eric (editor), Taekwondo Times Vol. 16, No. 8. Tri-Mount Publications, Iowa 1996. "The Beginning of Hapkido; An Interview with Hapkido Master Seo, Bok-Seob" by Mike Wollmershauser.
- Kim, He-Young. Hapkido (alternately The Hapkido Bible). Andrew Jackson Press, Baton Rouge, Louisiana 1991.
- Posthumously Released Interview with Choi Yong-Sool (1982).
- Scott Shaw (1996). Hapkido: Korean Art of Self-Defense. Boston, Massachusetts: Tuttle Publishing. ISBN 0-8048-2074-0.
- Pranin, S. (1988). Aikido Journal, AikiNews, 77. Interview with Kisshomaru Ueshiba: The Early Days of Aikido.
- http://www.segye.com/Articles/NEWS/CULTURE/Article.asp?aid=20100216002847&subctg1=&subctg2= (Korean)
- (Korean) 이소룡과 대결했던 합기도고수 지한재 방한 세미나 2010.01.12 chosun.com
- Kim, Jeong-Yoon. Personal interview with Matthew Rogers. Seoul. 1995.
- Spiedel, Rod. "Yong Sool Kwan; History of the Hapkido Hapkisul Headquarters". Taekwondo Times. Nov. 2006/Vol.26. No.6. Article compiled by Barrie Restall.
- Stepan, Charles (editor). Taekwondo Times Magazine. May 2005/Volume.25, No.3. Tri-Mount Publications, Iowa. Article by Sheryl and D'Aloia Michael "Mysterious Charm of Hapkido Granmaster Lim, Hyun-Soo". pg. 30.
- Master Park
- Hapkido Family Tree
- Giordano, Vincent (2003). Hidden Masters of the Martial Arts. New York City: Unpublished manuscript.
- Giordano, Vincent (May 12, 2006). Interview with Doju Chinil Chang. New York City: Personal interview.
- Giordano, Vincent (February 1, 2013). Interview with Doju Chinil Chang. New York City: Personal interview.
- Jong bae, Rim; Sheya, Joe; Burke, Mike (June 1999). "Birth of Hapkido: Founder Choi Yong-sul Reveals the Truth About the Art’s Origin". Black Belt Magazine: 130–139.
- Giordano, Vincent (August 1999). "Hapkido History Heresy?". Black Belt Magazine: 43.
- "The late Choi Bok-Yoel as second successor of Hapkido". http://www.hapkiyusul.com/eng/m2.htm.
- "Kim Yung Sang as third successor of Hapkido". http://www.hapkiyusul.com/eng/m3.htm.
- Restall, Barry (November 2006). "Young Sul Kwan: History of the Korean Hapkido Hapkiyusul Headquarters". Tae Kwon Do Times: 24–28.
- Chang, Chinil (April 1987). "Hapkido Founder Choi Passes On". Black Belt Magazine: 16.
- Young, Robert (January 1994). "Jujutsu vs. Hapkido". Black Belt Magazine: 26–31.
- Kim, He-Young. Hapkido II. Andrew Jackson Press, Baton Rouge, Louisiana 1994.
- Myung, Kwang-Sik. Korean Hapkido; Ancient Art of Masters. World Hapkido Federation, Los Angeles, California 1976.