<https://www.serpentinabooks.com/roy-m---the-principles-of-homoeopathic-philosophy-595-p.asp#product/595>
<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
<https://www.serpentinabooks.com/roy-m---the-principles-of-homoeopathic-philosophy-595-p.asp>