The International Standard Music Number (ISMN) is based on an ISO International Standard that was first published in 1993 as ISO 10957. 
ISO 10957 specifies the basic structure of an ISMN, the rules for its allocation, and the administration of the ISMN system. ISO 10957 is currently under revision to deal with changes to the ISMN system. For further information concerning the project status of the revision please contact the following URL:

Copies of ISO 10957 will be available for purchase from the International Organization for Standardization (ISO) and its national member organizations.