cover letter is what you write when you submit the article. "Enter common"? I do not know. Where did you get that expression? Not clear.

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3楼: Originally posted by charleszyc at 2017-08-19 09:14:08
springer投稿中遇到的一个选项

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But it says in the image "Enter Comments".  You wrote "enter commons".

Comments are simply a message you want to tell the Editor. If you write something there It's not seen by the reviewers. It's not normally used.

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5楼: Originally posted by charleszyc at 2017-08-19 09:23:30
sorry，我看错了。感谢您的耐心回复。那我把cover letter粘贴到那，合适吗？
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Possibly yes. But the system for journal submissions is different for different journals. There are now more and more journals that do not require to upload  a standard "cover letter" in word document, so what I do is to copy and paste my cover letter in the "comments". If in the upload section there is an option to upload cover letter, then that's the place to send it.

If you send me a pic after clicking in the link "comments" and show me  the page I may be able to tell you

if you do not want to show it here you can contact me by email, the way you prefer

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