1. Convention on the Rights of Persons with Disabilities.
http://www.un.org/disabilities/convention/conventionfull.shtml
. Accessed 25 Sept 2017
2. Nomura, M., Nielsen, G., Tronbacke, B.: Guidelines for easy-to-read materials.
http://www.ifla.org/files/assets/hq/publications/professional-report/120.pdf
3. Susanne, G.: Regeln und Standards für leicht verständliche Sprache. Leicht Lesen: Der Schlüssel zur Welt, pp. 88–105 (2015)
4. Digital Single Market.
https://ec.europa.eu/digital-single-market/en/policies/creating-digital-society
. Accessed 23 Sept 2017
5. Web Content Accessibility Guidelines (WCAG 2.0).
https://www.w3.org/TR/WCAG20/
. Accessed 25 Sept 2017