paracordguild.com have come with tutorial to tie the crown knot. The crown knot is classified in the Ashley book of knots under knob/terminal knots (under the number 670). More information here: http://www.paracordguild.com/tie-crown-knot/
Text from YouTube: This tutorial was made by viewer request and demonstrates how to tie the crown knot and how to add strands to it. This knot is often used to make keychains, bracelets and even leashes. It also serves as a transitional knot with which you can tie the turk’s head terminal knot and other stopper knots. It can also serve as a semi permanent finish for a round braid. It holds it in place nicely while you work on a more permanent knot. All in all, I consider this knot to be extremely important. It would probably get into the top 10 most important knots you need for working with rope and paracord.