| 摘要 |
Improvements to the construction of parquet flooring for sports courts, in which, on each and every one of the pieces of wood which form the parquet flooring for the playing courts, is made at least one transverse through- hole into which is inserted a rod with helically threaded ends of sufficient length for simultaneously threading on one or more other tongue-and-groove pieces joined together by means of transverse screwing. <IMAGE>
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