[90th anniversary of the discovery of roentgen radiation].
D049671:History, 18th Century; D049673:History, 20th Century; D011859:Radiography / Q000266:history*; D011878:Radiotherapy / Q000266:history*; D012425:Russia (Pre-1917); D014586:USSR
K 90-letiiu otkrytiia rentgenovskogo izlucheniia.