Metadata Metadata related to the material. copyright Copyright information. Pattern: ^\\(C\\) \\d{4}-\\d{4}, .+$ Required: Yes generator Software or tool used to generate the material. Required: Yes openmaterial_version Version of OpenMATERIAL. Pattern: ^\\d+\\.\\d+\\.\\d+$ Required: Yes creator Creator of the material. Required: Yes creation_date Date when the material was created, in the format YYYYMMDDTHHMMSSZ. Pattern: ^\\d{8}T\\d{6}Z$ Required: Yes material_version Version of the material. Pattern: ^\\d+\\.\\d+\\.\\d+$ Required: Yes id Unique identifier for the material. Pattern: ^[a-f0-9]{32}$ Required: Yes name Name of the material. Required: Yes description Description of the material. Required: Yes