Apparatus for sinking wells in the ground
AssigneeInstitut Gornogo Dela Sibirskogo Otdelenia Akademii Nauk SSSR
InventorsAndron T. Karavaev, Vladimir D. Plavskikh, Alexei D. Terskov, Anatoly V. Sukhushin, Nikolai P. Chepurnoi, Evgeny N. Cherednikov
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