回複：如何向一個不認識的教授要推薦信

You may want to wait for a first-author paper... Recently I saw quite a few RFE cases where people were asked about their role in the research, e.g, you need to play the major role in your research. A first-author paper would be the evidence to show that you are the main contributor of the paper.

About the letter, you may want to ask people you know through conferences, and people who cited your work before.

Good luck.

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