[Koha] Add Additional Patron attributes to Patron quickadd form

[Mai]

​​Hi,
I'm running Koha 16.11 on debian 8.
I've created an authorised value category called "TIPO_PERSONAL", added a
new patron attribute ​type named "RELACION" and linked it to that
authorized value category.
It appears correctly in the full form but I need this extended attribute to
display in the Quick add patron form as well.
I've​ ​edited the syspref PatronQuickAddFields​ to display other fields,
such as address, but in this case​ I don't know the ​n​ame of the field to
add. What can I do?
Thanks in advance,

-- 
Maite Arakaki