Title: Materialy 1-go Mezhdunarodnogo simpoziuma "Ivan Efremov - uchenyĭ, myslitelʹ, pisatelʹ, vzgli︠a︡d v 3-e tysi︠a︡cheletie
Subjects: Congresses, Paleontologists
Places: Soviet Union
People: Ivan Antonovich Efremov (1907-1972)