My husband does not have an original birth certificate... he says that he has always used his class 10th certifiate, which carries his date of birth, as birth certificate... will it be accepted while filing I-485? What have you guys used as a birth certificate? What document can be used in case an original certificate is not available? I read through the uscis website and the instructions in the forms, but I could not find anything mentioning an alternative to original birth certificate. As always... appreciate replies and time from you all. 
USC
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