Address book - add a new field

[Antonin]

I am trying already 2nd day to add 1 new field called "Tax Identification Number" to my osc2.3.1 ´s ADDRESS BOOK.

I succeeded with adding it to account information. Account information are ok.

 

But the address book information aren´t. When I open my address book at my site, I can only edit "company name", which is there as a default. I want to add there this new field.

I cant find the file where to add it. It is not the address_book.php nor address_book_process.php, these 2 contain mostly php but nearly no html. And also no file that has something to do with the account. Have you any idea?

Thanks

Antonin