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Gassprgert DZM. Hamburg Deutsches Zollmuseumbr Gassprgert zur Bestimmung der COKonzentration in Containern und abgedichteten Behltern zur Feststellung darin befindlicher Personen Grenzzollamt Gterverkehr Strae DZM own own photograph Photo Andreas Praefcke Own work all rights released Public domain Collections of the Deutsches