United States. Library of Congress, Savage, H., Droste, K. D., & Runshock, R. (1987). Library of Congress classification schedules combined with additions and changes through 1986 Class P : Language and literature: Subclasses P-PM supplement index to language and dialects. Gale Research Inc.
Chicago-viite (17. p.)United States. Library of Congress, Helen Savage, Kathleen D. Droste, ja Rita Runshock. Library of Congress Classification Schedules Combined with Additions and Changes Through 1986 Class P : Language and Literature: Subclasses P-PM Supplement Index to Language and Dialects. Detroit: Gale Research Inc, 1987.
MLA-viite (9. p.)United States. Library of Congress, et al. Library of Congress Classification Schedules Combined with Additions and Changes Through 1986 Class P : Language and Literature: Subclasses P-PM Supplement Index to Language and Dialects. Gale Research Inc, 1987.