This text aiming at the difficulty of subsided column currently in coal mine, launches the discussion.

本文讨论了高密度电法探测煤田陷落柱的若干问题。

youdao

This text aiming at the difficulty of subsided column currently in coal mine, launches the discussion.

本文讨论了高密度电法探测煤田陷落柱的若干问题。

youdao