It seems you're asking for a paper on — most likely referring to the CIP (Codi d'Identificació Personal) Salut , which is the Personal Health Identification Code used in Catalonia, Spain .
: Only doctors from the public system can issue official "sick leave" certificates (baixa) for your employer, making the CIP indispensable even for those who primarily use private insurance. How to Obtain Your CIP cip salut
The CIP operates under: