TA Engineering (General). Civil engineering (General) 56 TK Electrical engineering. Electronics Nuclear engineering 35 TH Building construction 30 QA75 Electronic computers. Computer science 25 QA76 Computer software 23 T Technology (General) 10 TJ Mechanical engineering and machinery 10 HD28 Management. Industrial Management 6 HD1394-1394.5 Real estate management 5 Unspecified 5 H Social Sciences (General) 4 HD Industries. Land use. Labor 3 HE Transportation and Communications 3 HG Finance 3 HT101-395 Sociology, Urban 3 K Law (General) 3 L Education (General) 3 TP Chemical technology 3 G70.212-70.215 Geographic information system 2 LB2300 Higher Education 2 QC Physics 2 QE Geology 2 TK5015.888 Web sites 2 TL Motor vehicles. Aeronautics. Astronautics 2 TS Manufactures 2 G Geography. Anthropology. Recreation 1 GE Environmental Sciences 1 HB Economic Theory 1 HC Economic History and Conditions 1 KD England and Wales 1