User talk:49.199.206.161

August 2021
Welcome to Wikipedia. We appreciate your contributions, but in one of your recent edits to NACA duct, it appears that you have added original research, which is against Wikipedia's policies. 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. You can have a look at the tutorial on citing sources. Thank you. BilCat (talk) 06:24, 13 August 2021 (UTC)