User talk:Yemen1990

Welcome to Wikipedia. We welcome and appreciate your contributions, but we cannot accept original research. Original research refers to material—such as facts, allegations, ideas, and personal experiences—for which no reliable, published sources exist; it also encompasses combining published sources in a way to imply something that none of them explicitly say. Please be prepared to cite a reliable source for all of your contributions. Thank you. Materialscientist (talk) 10:11, 12 May 2016 (UTC)