Library of Congress. Subject Cataloging Division, Gale Research Company, & Library of Congress. Classification Division. (1980). Library of Congress classification schedules: a cumulation of additions and changes through 1978: Class Q, Science. Gale Research Co..
توثيق أسلوب شيكاغو (الطبعة السابعة عشر)Library of Congress. Subject Cataloging Division, Gale Research Company, و Library of Congress. Classification Division. Library of Congress Classification Schedules: A Cumulation of Additions and Changes Through 1978: Class Q, Science. Detroit: Gale Research Co., 1980.
توثيق جمعية اللغة المعاصرة MLA (الطبعة الثامنة)Library of Congress. Subject Cataloging Division, et al. Library of Congress Classification Schedules: A Cumulation of Additions and Changes Through 1978: Class Q, Science. Gale Research Co., 1980.