Origami –

https://en.wikipedia.org/wiki/Origami

Heart Symbol –

https://en.wikipedia.org/wiki/Heart_symbol#Encoding 

“Easiest Origami Heart Ever! – Tutorial in English (BR)”, Easy Origami –

https://youtu.be/Z-BIL6p1Te8 

“How to make an origami heart” –

https://www.origamiway.com/origami-heart.shtml 

Illustrations –

https://i0.wp.com/origami.guide/wp-content/uploads/2019/03/easy-origami-heart-tutorial-00-1.jpg?fit=1920%2C1920&ssl=1

http://www.basaltlibrary.org/uploads/1/1/2/9/112997625/steps-to-folding-an-origami-heart-from-square-piece-of-paper-kids-activities-blog_orig.jpg

https://i0.wp.com/homemadeheather.com/wp-content/uploads/2021/12/Heart-origami-01-600×776.jpg