ARL Statistics. Association of Research Libraries.
Chicago Style (17th ed.) CitationARL Statistics. Association of Research Libraries.
MLA引文ARL Statistics. Association of Research Libraries.
警告：這些引文格式不一定是100％准確.
APA引文
ARL Statistics. Association of Research Libraries.
Chicago Style (17th ed.) CitationARL Statistics. Association of Research Libraries.
MLA引文ARL Statistics. Association of Research Libraries.