DOI or direct object identifier is one of key elements of each article in a journal. Editors of the journals must have basic knowledge to check the validity of DOI of their published articles. Using this flowchart, editors are able to check or control the validity of DOI's in their journals.
DOI is a unique identifier of each article which must be registered and maintained by the journal publisher. Unfortunately, many non-publisher organizations are presenting this important service as a separate service to the journals. On the other hand, many mono-journal publishers are trying to register themselves as a new publisher and register their required DOI. Especially in low-income countries or non-developed countries, the tendency of mono-journal publishers to register DOI are higher than other countries. In this flowchart, we are trying to give a clue to the editors about the validity of DOI in their journals.