kevin1020

here is what you want , just get it.

study

It is shockingly expensive！！

kevin1020

just a little cost, not mind

but  it's really an result of long time experience.

venom1993

Cost too much, the first item could not be downloaded, but I paid.

sdwalker

Thank you very much!

ducaixia

It should be free!

夜雨成冰

Thank for your english datas,i am working hard at  learning the metallurgy professional english.maybe our factory make more comunication about alumina technology with foreign expert ,i am intrereing with it and starting again to learn it .it is usful of getting more knowledge if you can use it agility and speakit wiith fluency.so i advise everyone coming here going on learning it !if you get it ,you can get more !