Robuta

https://www.faa.gov/regulations_policies/orders_notices/index.cfm/go/document.information/documentID/1044958 Notice JO 7340.909 - Cancellation of Defunct U.S. ICAO Call Signs and Three Letter Designators The Federal Aviation Administration is an operating mode of the U.S. Department of Transportation. https://lists.w3.org/Archives/Public/public-tt/2014Jun/0017.html IMSC feature designators from Nigel Megitt on 2014-06-13 (public-tt@w3.org from June 2014) https://id.loc.gov/vocabulary/rbmsrel.html Rare Books and Manuscripts Relationship Designators - LC Linked Data Service: Authorities and... rare books and manuscripts linked data service relationship