Q Science (General) 33 QA75 Electronic computers. Computer science 18 TA Engineering (General). Civil engineering (General) 10 QD Chemistry 5 GE Environmental Sciences 4 HD28 Management. Industrial Management 4 TH Building construction 3 H Social Sciences (General) 2 LB Theory and practice of education 2 TK Electrical engineering. Electronics Nuclear engineering 2 G70.212-70.215 Geographic information system 1 HD61 Risk Management 1 JA Political science (General) 1 L Education (General) 1 NA Architecture 1 QA76 Computer software 1 QC Physics 1 QH Natural history 1 T Technology (General) 1 TD Environmental technology. Sanitary engineering 1 TH434-437 Quantity surveying 1 TJ Mechanical engineering and machinery 1 V Naval Science (General) 1 Z665 Library Science. Information Science 1