excel_date_cells        Find the cells a workbook formats as dates
excel_date_columns      Summarise date-formatted cells by column
excel_date_system       Read the date system a workbook declares
excel_origin            The origin date behind each Excel date system
excel_sheets            List the sheets in a workbook
fix_serial_columns      Revert Excel date serials across a data frame
restore_day_month       Revert Excel date serials in an
                        already-imported vector
serial_to_day_month     Convert Excel date serials to 'day.month'
                        values
unexcel_xlsx            Read an '.xlsx' sheet and undo its date
                        auto-conversion
