When using numbers or letters to enumerate lists within sentences, enclose the numbers or
letters in parentheses. In addition, do not place a colon after a preposition (to).
United States – BUSPROG.BENG.GUFF.17.6.6 – DISC.BENG.GUFF.17.6.6
United States – BUSPROG.BENG.GUFF.17.6.7 – DISC.BENG.GUFF.17.6.7