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Priority claimed from NL6504741.Aexternal-prioritypatent/NL155947B/xx
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Publication of BE713278ApublicationCriticalpatent/BE713278A/xx
E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
E21B25/00—Apparatus for obtaining or removing undisturbed cores, e.g. core barrels or core extractors
E21B25/06—Apparatus for obtaining or removing undisturbed cores, e.g. core barrels or core extractors the core receiver having a flexible liner or inflatable retaining means