title: [Petr Petrovich Kovalenko (on his 60th birthday)].
mesh_terms: D000818:Animals; D002417:Cattle; D013502:General Surgery / Q000266:history; D006666:History of Medicine; D012426:Russia
vernacular_title: Petr Petrovich Kovalenko (k 60-letiiu so dnia rozhdeniia).