4 · Society, Civilization, Culture
46 · social and economic life, transport and communication
46C · traffic and transport
46CC21 · ships (in general) - CC - more than one ship
46CC21(+2) · ships (in general) - CC - more than one ship (+ number of persons ~ traffic and transport)
46CC21(+23) ·
ships (in general) - CC - more than one ship (+ three persons ~ traffic and transport)