BROWN, James Duff. Subject classification, with tables, indexes, etc., for the sub-division of subjects. London: Library Supply, 1906. 423 s.
ark:/13960/t57d38s3p. Digitální kopie (2008, dle exempláře Michiganské univerzity) dostupná z Internet Archive: http://archive.org/details/subjectclassifi02browgoog.