MIXED is the parameter for the STYLE specification of BRconfig.sys which indicates that the text it refers to should be listed with the first letter in uppercase and the remaining letters in lowercase.
The MIXED parameter's effect on comments varies according to the type of comment. If the comment follows a Business Rules statement the first letter of the first word will be uppercase and the rest will be lowercase. If the comment does not follow a statement (if it is alone on a line, for instance), the first letter of each word is uppercase and the rest are lowercase. Capitalization specifications may be disabled for individual comments when the first character in the comment is a period (.).