Chenille is writing a research paper about the effects of over-the-counter teeth whitening products on tooth enamel. Her thesis is that over-the-counter products may be harmful. She has decided to use the internet for part of her research study. After doing a search for information, she comes across an article on the homepage for the American Dental Association about the effects of over-the-counter teeth whiteners. The article is credited to Dr. Susan Leeds, a cosmetic dentist from New York and says that over-the-counter teeth whiteners are not harmful but may not be very effective. She bookmarks the site and continues to research. Later, she comes across a website called White Teeth Now. There is a commentary that is written by an anonymous source about how over-the-counter whiteners can lead to more cavities and sensitive gums. What is one way for Chenille to decide which source is more credible?