Where can I find DB:link_attribute_type/name strings in the wild?

Tags: #<Tag:0x00007fe315385a68>

There are a couple of strings on Transifex that I can’t place: “classical music” (DB:link_attribute_type/name:1204:), “musical education” (DB:link_attribute_type/name:1202:), “music production” (DB:link_attribute_type/name:1201:), “popular / rock music” (DB:link_attribute_type/name:1200:), “singing” (DB:link_attribute_type/name:1199:) and “music therapy” (DB:link_attribute_type/name:1203:).
Could someone point me in the right direction?