本文介绍，源于Cranes Etc 网站（ http://www.cranesetc.co.uk/）的测评文章，本文仅做中文简要介绍。
This article is just a brief introduction to the topic on the Cranes Etc website (http://www.cranesetc.co.uk/).
有关 Cranes Etc 网站 的中文介绍请见：http://www.cranesetc.co.uk/welcome/chinese.htm
The figures were developed and made by Bhaskar Chowdhury, Maqbool Ahmed Abbasi and LRSM
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All copyrights belong to ( Cranes Etc), and many thanks to the author of the site!
