US. Congress. (1968). Official congressional directory: For the use of the United States Congress ; closing date for compiling directory material, December 15, 1967. United States Government Printing Office.
芝加哥风格引文US. Congress. Official Congressional Directory: For the Use of the United States Congress ; Closing Date for Compiling Directory Material, December 15, 1967. Washington: United States Government Printing Office, 1968.
MLA引文US. Congress. Official Congressional Directory: For the Use of the United States Congress ; Closing Date for Compiling Directory Material, December 15, 1967. United States Government Printing Office, 1968.
警告：这些引文格式不一定是100％准确.