This is actually the range assigned to the write-up with the publisher, and it's the 1 you'll use to reference your write-up throughout the library catalogues. ISSN code (also known as as "ISSN structure" or "ISSN syntax") may be expressed as follows: NNNN-NNNC The complexity with the peer evaluate approach https://www.directivepublications.org/journal-of-applied-nanoscience/