Some databases use standardized terminology in order to identify items in their respective databases. This means that they have a consistent way of referring to each author, even those that are known by different names or have multiple spellings of their names. When standardized terminology is used, the database will refer you to the form of name being used. Look for an author list that you can either browse or search by keyword.  Note in the library search box if you search "Chartier Emile Auguste" the system will automatically bring up works by Alain (the form of name being used for material in the library collection)

If the database you are using does not have a standardized way of referring to names and you think the person you are looking for may have more than one name use a reference tool such as the Gale Virtual Reference Library to locate alternate forms of the name.