[The letter in edition].
D000846:Anniversaries and Special Events; D049673:History, 20th Century; D049674:History, 21st Century; D006772:Hospitals, Military / Q000266:history* / Q000458:organization & administration; D006801:Humans; D008887:Military Medicine / Q000266:history* / Q000379:methods / Q000458:organization & administration; D012426:Russia