AC - Collections. Series. Collected works
AE - Encyclopedias
AG - Dictionaries and other general reference works
AI - Indexes
AM - Museums. Collectors and collecting
AN - Newspapers
AP - Periodicals
AS - Academies and learned societies
AY - Yearbooks. Almanacs. Directories
AZ - History of scholarship and learning. The humanities
B - Philosophy (General)
BC - Logic
BD - Speculative philosophy
BF - Psychology
BH - Aesthetics
BJ - Ethics
BL - Religions. Mythology. Rationalism
BM - Judaism
BP - Islam. Bahaism. Theosophy, etc.
BQ - Buddhism
BR - Christianity
BS - The Bible
BT - Doctrinal theology
BV - Practical Theology
BX - Christian Denominations
C - Auxiliary Sciences of History
CB - History of Civilization
CC - Archaeology
CD - Diplomatics. Archives. Seals
CE - Technical Chronology. Calendar
CJ - Numismatics
CN - Inscriptions. Epigraphy
CR - Heraldry
CS - Genealogy
CT - Biography
D - History (General)
DA - Great Britain
DAW - Central Europe
DB - Austria - Liechtenstein - Hungary - Czechoslovakia
DC - France - Andorra - Monaco
DD - Germany
DE - Greco-Roman World
DF - Greece
DG - Italy - Malta
DH - Low Countries - Benelux Countries
DJ - Netherlands (Holland)
DJK - Eastern Europe (General)
DK - Russia. Soviet Union. Former Soviet Republics - Poland
DL - Northern Europe. Scandinavia
DP - Spain - Portugal
DQ - Switzerland
DR - Balkan Peninsula
DS - Asia
DT - Africa
DU - Oceania (South Seas)
DX - Romanies
11-143 - America
151-909 - United States
1-975 - United States local history
1001-1145.2 - British America (including Canada) Dutch America
1170 - French America
1201-3799 - Latin America. Spanish America
G - Geography (General). Atlases. Maps
GA - Mathematical geography. Cartography
GB - Physical geography
GC - Oceanography
GE - Environmental Sciences
GF - Human ecology. Anthropogeography
GN - Anthropology
GR - Folklore
GT - Manners and customs (General)
GV - Recreation. Leisure
H - Social sciences (General)
HA - Statistics
HB - Economic theory. Demography
HC - Economic history and conditions
HD - Industries. Land use. Labor
HE - Transportation and communications
HF - Commerce
HG - Finance
HJ - Public finance
HM - Sociology (General)
HN - Social history and conditions. Social problems. Social reform
HQ - The family. Marriage, Women and Sexuality
HS - Societies: secret, benevolent, etc.
HT - Communities. Classes. Races
HV - Social pathology. Social and public welfare. Criminology
HX - Socialism. Communism. Anarchism
J - General legislative and executive papers
JA - Political science (General)
JC - Political theory
JF - Political institutions and public administration
JJ - Political institutions and public administration (North America)
JK - Political institutions and public administration (United States)
JL - Political institutions and public administration (Canada, Latin America, etc.)
JN - Political institutions and public administration (Europe)
JQ - Political institutions and public administration (Asia, Africa, Australia, Pacific Area, etc.)
JS - Local government. Municipal government
JV - Colonies and colonization. Emigration and immigration. International migration
JX - International law, see JZ and KZ (obsolete)
JZ - International relations
K - Law in general. Comparative and uniform law. Jurisprudence
KB - Religious law in general. Comparative religious law. Jurisprudence
KBM - Jewish law
KBP - Islamic law
KBR - History of canon law
KBS - Canon law of Eastern churches
KBT - Canon law of Eastern Rite Churches in Communion with the Holy See of Rome
KBU - Law of the Roman Catholic Church. The Holy See
Subclasses - KD/KDK - United Kingdom and Ireland
KDZ - America. North America
KE - Canada
KF - United States
KG - Latin America - Mexico and Central America - West Indies. Caribbean area
KH - South America
KJ-KKZ - Europe
KL-KWX - Asia and Eurasia, Africa, Pacific Area, and Antarctica
KU/KUQ - Law of Australia and New Zealand
KZ - Law of nations
L - Education (General)
LA - History of education
LB - Theory and practice of education
LC - Special aspects of education
LD - Individual institutions - United States
LE - Individual institutions - America (except United States)
LF - Individual institutions - Europe
LG - Individual institutions - Asia, Africa, Indian Ocean islands, Australia, New Zealand, Pacific islands
LH - College and school magazines and papers
LJ - Student fraternities and societies, United States
LT - Textbooks
M - Music
ML - Literature on music
MT - Instruction and study
N - Visual arts
NA - Architecture
NB - Sculpture
NC - Drawing. Design. Illustration
ND - Painting
NE - Print media
NK - Decorative arts
NX - Arts in general
P - Philology. Linguistics
PA - Greek language and literature. Latin language and literature
PB - Modern languages. Celtic languages and literature
PC - Romanic languages
PD - Germanic languages. Scandinavian languages
PE - English language
PF - West Germanic languages
PG - Slavic languages and literatures. Baltic languages. Albanian language
PH - Uralic languages. Basque language
PJ - Oriental languages and literatures
PK - Indo-Iranian languages and literatures
PL - Languages and literatures of Eastern Asia, Africa, Oceania
PM - Hyperborean, Native American, and artificial languages
PN - Literature (General)
PQ - French literature - Italian literature - Spanish literature - Portuguese literature
PR - English literature
PS - American literature
PT - German literature - Dutch literature - Flemish literature since 1830 - Afrikaans literature -Scandinavian literature - Old Norse literature: Old Icelandic and Old Norwegian - Modern Icelandic literature - Faroese literature - Danish literature - Norwegian literature - Swedish literature
PZ - Fiction and juvenile belles lettres
Q - Science (General)
QA - Mathematics
QB - Astronomy
QC - Physics
QD - Chemistry
QE - Geology
QH - Natural history - Biology
QK - Botany
QL - Zoology
QM - Human anatomy
QP - Physiology
QR - Microbiology
R - Medicine (General)
RA - Public aspects of medicine
RB - Pathology
RC - Internal medicine
RD - Surgery
RE - Ophthalmology
RF - Otorhinolaryngology
RG - Gynecology and Obstetrics
RJ - Pediatrics
RK - Dentistry
RL - Dermatology
RM - Therapeutics. Pharmacology
RS - Pharmacy and materia medica
RT - Nursing
RV - Botanic, Thomsonian, and Eclectic medicine
RX - Homeopathy
RZ - Other systems of medicine
S - Agriculture (General)
SB - Horticulture. Plant propagation. Plant breeding
SD - Forestry. Arboriculture. Silviculture
SF - Animal husbandry. Animal science
SH - Aquaculture. Fisheries. Angling
SK - Hunting
T - Technology (General)
TA - Engineering Civil engineering (General).
TC - Hydraulic engineering. Ocean engineering
TD - Environmental technology. Sanitary engineering
TE - Highway engineering. Roads and pavements
TF - Railroad engineering and operation
TG - Bridges
TH - Building construction
TJ - Mechanical engineering and machinery
TK - Electrical engineering. Electronics. Nuclear engineering
TL - Motor vehicles. Aeronautics. Astronautics
TN - Mining engineering. Metallurgy
TP - Chemical technology
TR - Photography
TS - Manufacturing engineering. Mass production
TT - Handicrafts. Arts and crafts
TX - Home economics
U - Military science (General)
UA - Armies: Organization, distribution, military situation
UB - Military administration
UC - Military maintenance and transportation
UD - Infantry
UE - Cavalry. Armor
UF - Artillery
UG - Military engineering. Air forces
UH - Other military services
V - Naval science (General)
VA - Navies: Organization, distribution, naval situation
VB - Naval administration
VC - Naval maintenance
VD - Naval seamen
VE - Marines
VF - Naval ordnance
VG - Minor services of navies
VK - Navigation. Merchant marine
VM - Naval architecture. Shipbuilding. Marine engineering
Z - Books (General). Writing. Paleography. Book industries and trade. Libraries. Bibliography
ZA - Information resources/materials
