<https://secure.gravatar.com/avatar/dc93d3b89a7e49c5e688e2c5f7257f48?s=96&d=mm&r=g>
<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
<https://www.kerabel.cz/vypocet-bmi-vam-stanovi-jak-jste-na-tom-se-svoji-telesnou-hmotnosti/>