<https://www.crochet.eu/crochet-ganchillo/tutoriales/single-crochet-ribbing-left-handed-tutorial/#webpage>
<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
<https://www.crochet.eu/crochet-ganchillo/tutoriales/single-crochet-ribbing-left-handed-tutorial/>