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I am a Green Card holder in the United States and do not have any passport from my country of citizenship. I want to visit my family in Germany and according to my research, I have to apply for Refugee Travel Document (I-131 form). I have also found that I do not need any visa to enter Germany for less than 3 months. I just wanted to confirm if I am not missing any details. Also what documents should I take with me when I do travel?