Operations research 514 Production and operations management--Product management 291 Operating systems (Computers) 176 Operating systems 161 History 142 Biography 140 Engineering & allied operations 120 Operational calculus-- Functional analysis-- Mathematics 109 Operations Research-- Information management-- Executive management 106 Operations management 100 Religion 99 Production and operations management 85 Economics 81 Operations Research--Information management--Executive management 80 Management 78 Co-operative management 76 Malayalam; Other Studies 74 Co operation 67 Microbiology 66 Bible & Other Sacred Texts 64 Operator theory 61 Mathematics 60 Philosophy 58 Others 57 Computer science 54 India 54 Social Sciences 53 Linear operators 50 മലയാളം; മറ്റുള്ളവ/മറ്റുള്ള പഠനങ്ങള്‍ 48 Botany 47