Page 158 - Bob Holtzman "The Field Guide to Knots How to Identify.."

4. Holding the standing part and working end together in one hand, pull the bight to tighten.

Untying: Grab either strand of the bight just before it passes under the
standing parts, and either strand of the standing part where it passes over the

bight, and pull in opposite directions. Generally, however, you should
consider this knot to be permanent and be prepared to cut it.

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