Periodicals 41 Directories 38 Dictionaries 34 Biography -- 21 Politics and government -- 19 Economic conditions -- 18 Periodicals -- 18 more ... Handbooks, manuals, etc 15 Politics and government 14 English language -- 13 Biography 12 Directories -- 12 International agencies -- 12 Yearbook 12 Government -- 11 Handbooks, manuals, etc. -- 11 World politics -- 11 Dictionaries -- 9 Economics -- 9 Social conditions -- 9 Statesmen -- 9 Yearbook -- 9 Arms control 8 Economic conditions 8 Guidebooks 8 History -- 8 Statistics 8 Encyclopedias and directories -- 7 Peacemaking -- 7 Security, International 7 less ...