TK Electrical engineering. Electronics Nuclear engineering 390 TA Engineering (General). Civil engineering (General) 353 TP Chemical technology 352 TJ Mechanical engineering and machinery 274 QA75 Electronic computers. Computer science 250 QA Mathematics 148 Q Science (General) 127 T Technology (General) 99 QD Chemistry 93 QC Physics 85 L Education (General) 64 HD28 Management. Industrial Management 59 QA76 Computer software 50 BP Islam. Bahaism. Theosophy, etc 49 HD1394-1394.5 Real estate management 36 TH Building construction 33 Q Science 32 LB2300 Higher Education 31 H Social Sciences (General) 30 HD Industries. Land use. Labor 29 TD Environmental technology. Sanitary engineering 24 TN Mining engineering. Metallurgy 22 R Medicine (General) 19 LB Theory and practice of education 17 LC Special aspects of education 17 T Technology 16 TH434-437 Quantity surveying 16 LB1603 Secondary Education. High schools 14 NA Architecture 14 HT101-395 Sociology, Urban 13