Are they really parentheses or are they curly brackets?
Those look like temporary endnote cites prior to “update citations and bibliography” command (manually) or auto updatding to the citations as defined in your output style. (if auto format is on), except they should look like this {Burnes, 1994 #1}.
But if you have changed your delimiters to normal parenthesis in either the format bibliography “menu” or in your preferences, you will have a lot of problems with regular parenthetical statments trying to be parsed by Endnote.