How Could I Get Reference Letter from Independent and Well-Recognized Expert for EB-1A Application

According to USCIS, the reference letter should come from independent and well-recognized expert, based upon his/her review of the documents that are submitted with the EB1 Extraordinary Ability application. By "independent", the USCIS means an expert with whom the alien application has not worked before - not an employer, colleague, advisor, or client. By "well-recognized", the USCIS means a well-credentialed expert with lengthy experience in the field of endeavor. The experience should include an advanced degree, more than ten years of experience in the field, a lengthy publication and presentation record. Not every EB-1A application case needs the reference letter from "independent" and "well-recognized expert", especially when the alien applicant has Ph.D. degree and a lengthy publication record and several wards, which could distinguish the alien applicant from other individuals in the field. http://www.greencardapply.com/question/question14/Independent-Reference-Letters_0303.htm