History 10 Social Sciences 7 Periodic law 6 Income tax--Taxes and Taxation--Public finance--Economics 5 Philosophy 5 Income tax 4 Income tax--law 4 Law and legislation 4 Poverty 4 Qualitative research 4 Social responsibility of business 4 Teaching 4 Tourism 4 United States 4 Women 4 Arts 3 Compilers (Computer programs) 3 Computational learning theory 3 Economics 3 Educational tests 3 Expert systems (Computer science) 3 Feminism 3 Financial Management 3 Health 3 Internet 3 Knowledge, Theory of 3 Latin American poetry 3 Management 3 Marketing research 3 Markov processes 3