Columbia subject headings:
Porphyria--Genetic aspects.
Royal houses--Europe.
Harvard subject headings:
Diseases and history--Europe.
Europe--Kings and rulers--Diseases.
Porphyria--Genetic aspects.
Porphyria.
Royal houses--Europe.
Princeton subject headings:
Europe--Kings and rulers--Health and hygiene.
Great Britain--Kings and rulers--Health and hygiene.
Porphyria--History.