1. DESCRIPTION OF THE DATA FIELD:

Variable size

Optional filling

2. DEFINITION OF DATA ELEMENT:

a) Digital Object Identifier (DOI) is a unique code – formed by a pattern of letters and numbers – for persistent digital identification of publications available on the internet.

3. NOTES:

a) The DOI number is located in the document or in the descriptive metadata of the work.

b) Only the code is recorded, excluding the URL part.

4. EXAMPLES:

10.1590/S0102 311X2008000500013