Religious aspects 227,315
Research 200,096
Religion 154,836
Relations 124,093
Railroads 84,161
Roads 65,607
Race relations 58,448
Religious life 45,936
Russian literature 41,016
Regional planning 40,836
Russian language 35,316
Rural conditions 34,953
Real property 34,541
Rock music 33,782
Religious life and customs 32,855
Reference 32,060
Rhetoric 30,922
Refugees 30,869
Rural development 29,035
Rites and ceremonies 28,231
Rules and practice 24,885
Regimental histories 24,184
Rehabilitation 24,019
Reformation 21,972
Racism 20,870
Readers 20,329
RELIGION 20,259
Reading 19,852
Revolutionaries 18,798
Radio 16,710
Russian poetry 15,443
Roman law 14,960
Religions 14,774
Russian 14,680
Rabbis 14,640
Romanticism 14,346
Responsa 14,186
Rivers 13,922
Rare books 13,900
Representative government and representation 13,866
Renaissance 13,713
Religion and science 13,641
Revolutions 13,609
Rituals 13,202
Relations extérieures 12,888
Registers of births, etc 12,570
Retirement 11,925
Renewable energy sources 11,545
Radicalism 11,348
Rates 11,190
Religion and politics 11,095
Reorganization 11,006
Russians 11,002
Remote sensing 10,909
Retail trade 10,839
Registration and transfer 10,805
Recherche 10,498
Romans 10,334
Rap (Music) 10,333
Risk management 10,066
Refuse and refuse disposal 9,888
Reproduction 9,541
Religious education 9,355
Registers 9,336
Regionalism 9,195
Revenue 9,063
Reformed Church 9,060
Race discrimination 9,027
Radio broadcasting 9,027
Riots 8,937
Religion and state 8,931
Recreation 8,808
Radiation 8,697
Robotics 8,472
Reconstruction (1939-1951) 8,380
Rock musicians 8,333
Risk assessment 8,280
Religion and sociology 8,024
Race identity 7,875
Restaurants 7,854
Recruiting, enlistment, etc 7,837
Romanies 7,431
Repentance 7,429
Reclamation of land 7,230
Requiems 7,217
Right and left (Political science) 7,157
Radiography 7,054
Research, Industrial 6,812
Revenge 6,728
Rice 6,628
Russian fiction 6,451
Rule of law 6,429
Romances 6,219
Real estate business 6,173
Relations with women 6,124
Rating of 5,958
Reconstruction (U.S. history, 1865-1877) 5,865
Race 5,843
Recruiting 5,839
Reform 5,747