Practice for subsurface installation of corrugated thermoplastic tubing for agricultural drainage or water table control 农业排水或地下水位控制用热塑塑料波纹管地下安装惯例
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Standard practice for subsurface installation of corrugated polyethylene pipe for agricultural drainage or water table control 农业排水或地下水位控制用聚乙烯波纹管地下安装的标准实施规范