Description and travel 411,122
Diplomatic relations 130,414
Diseases 114,079
Doctrines 103,766
Data processing 76,643
Dictionaries 70,663
Democracy 63,675
Design and construction 62,582
Drama 59,237
Dialects 53,008
Death 42,905
Directories 37,924
Discovery and exploration 36,211
Design 32,460
Documentary films 28,172
Drugs 27,051
Diagnosis 26,435
Dwellings 26,294
Development 24,972
Decision making 24,964
Defenses 23,797
Debts, Public 21,691
Dance 21,680
Drawing 19,772
Discoveries in geography 18,780
Drug abuse 18,036
Death and burial 17,476
Dance music 17,474
Decoration and ornament 16,282
Discourse analysis 15,276
Dogs 15,155
Diseases and pests 14,918
Designs and plans 14,689
Droit 14,553
Decorative arts 14,495
Diaries 14,285
Divorce 13,986
Disaster relief 13,912
Domestic relations 13,625
Database management 12,910
Digital techniques 11,792
Discipline 11,787
Diplomats 11,711
Discrimination in employment 11,267
Drug control 11,043
Data mining 10,946
Dance orchestra music 10,898
Diet 10,726
Dissenters, Religious 10,559
Data protection 10,059
Dissertations, Academic 10,055
Decoration and ornament, Architectural 9,961
Drug traffic 9,658
Demography 9,562
Detective and mystery stories 9,407
Descriptions et voyages 9,274
Democratization 9,270
Doctrinal and controversial works 9,009
Dreams 8,917
Decentralization in government 8,874
Dentistry 8,823
Databases 8,661
Defense contracts 8,578
Debtor and creditor 8,552
Diplomatic history 8,527
Delivery of Health Care 8,478
Disarmament 8,251
Dissertations 8,069
Differential equations 7,405
Dialectical materialism 7,384
Drug use 7,294
Disasters 7,212
Discrimination 7,173
Documentary photography 7,134
Debts, External 6,975
Dams 6,876
Dispute resolution (Law) 6,800
Digital media 6,747
Draft 6,668
Deeds 6,601
Damages 6,525
Diplomatic and consular service 6,395
Devotional literature 6,216
Discrimination & Race Relations 6,178
Defense industries 6,113
Diplomacy 6,095
Differential equations, Partial 6,076
Debt 5,965
Dynamics 5,960
Développement 5,899
Depressions 5,807
Diabetes 5,668
Dutch language 5,653
Dissenters 5,519
Details 5,447
Dutch 5,310
Divination 5,180
Deaf 5,169
Demonstrations 5,145
Demonology 5,022