that lasts two lustra, i. e. ten years , of ten years ' duration

http://lila-erc.eu/data/lexicalResources/LewisShort/id/LexicalSense/n5347.0 an entity of type: LexicalSense

that lasts two lustra, i. e. ten years , of ten years ' duration 
that lasts two lustra, i. e. ten years , of ten years ' duration 

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