[Nikolaĭ Nikolaevich Petrov (on the 90th anniversary of his birth)].
D049672:History, 19th Century; D049673:History, 20th Century; D009369:Neoplasms / Q000266:history; D014586:USSR
Nikolaĭ Nikolaevich Petrov (k 90-letiiu so dnia rozhdeniia)