Ude-Hishigi-Sankaku-Gatame is one of the official 29 grappling techniques of Kodokan Judo. It is one of the
nine
joint techniques of the
Kansetsu-waza list,
one of the three grappling lists in Judo's Katame-waza
http://www.judoinfo.com/gokyo3.htm
enumerating 29 grappling techniques.http://www.judoinfo.com/gokyo2.htm

Technique Description

Graphic
from
http://www.jigorokano.it/Cartella%20Gruppi/Kansetsu%20Waza.html

Included Systems

Systems:

• Kodokan
  Kodokan
  , or the Kodokan Institute, is the headquarters of the worldwide judo community. Literally, kō means "to lecture" or "to spread information," dō means "the way," and kan is "a public building or hall," together translating roughly as "a place for the study or promotion of the way." The Kodokan was...
  
   Judo
  Judo
  is a modern martial art and combat sport created in Japan in 1882 by Jigoro Kano. Its most prominent feature is its competitive element, where the object is to either throw or takedown one's opponent to the ground, immobilize or otherwise subdue one's opponent with a grappling maneuver, or force an...
  
  , List of Kodokan Judo techniques

Lists:

• The Canon Of Judo
• Judo technique
  Judo technique
  This page is a list of judo techniques. There are a variety of techniques recognized by Kodokan judo and other budō . Below is a partial list, organized by technique type and alphabetically within type....
  
  

Ao-Muke-Gata-Ude-Hishigi

Ao-Muke-Gata-Ude-Hishigi is described in the Canon Of Judo and
demonstrated by Kyuzo Mifune

Kyuzo Mifune

has been categorized as one of the greatest exponents of the art of judo after the founder, Kanō Jigorō. He is considered by many to be the greatest judo technician ever, after Kanō.-Early life:...

in the video,
The Essence of Judo.