Louis’s is a more popular single possessive for Louis. It’s also the form that is stipulated by the Chicago Manual of Styles. E.g.,” Louis’s car…

The term Ross’s is the more common way to form the singular possessive of Ross. E.g., “Ross’s office is well-organized.” However, the word Ross’ without…

The  singular possessive form of business is “business’.” E.g., “The business’ revenue increased steadily over the years.” However, the alternative possessive form “business’s”  ending with…