| ↑ | 004 | hardware, networks, computer science generally |  → 519.4 621.39 ≈ :P.0 |
| ↑ | 006.6 | digital images | → 550.28 620.0042 621.36 |
| ↑ | 333.7 | natural resources, energy | → 338.927 354 621.31 720.47 |
| ↑ | 530.14 | fields and waves | → 621.3813 |
| ↑ | 535 | optics | → 621.36 ≈ :ZA.7 |
| ↑ | 539.2 | radiations | → 621.382 |
| ↑ | 550.28 | remote sensing | → 006.6 526.9 621.367 910.28 ≈ `17C OE11 |
| ↑ | 621.369 | fiber, integrated, nonlinear optics | → 621.3827 |
| ↑ | 621.3815 | components and circuits, CMOSs | → 621.395 681 |
| ↑ | 621.3827 | optical communication and fibers | → 621.369 |
| ↑ | 621.395 | logical networks, VLSI | → 621.3815 681 |
| ↑ | 681 | precision instruments | → 621.3815 |
| ↑ | 729.28 | lighting | → 621.32 690.18 |
| AC | congressional acts (elect.) | ≈ 621.3 |
| ↑ | AF2 | reliability of the equipment and electronic systems | ≈ 620.11 621.38 |
| ↑ | AF7 | congresses (electr. reliability) | ≈ 620.11 621.31 |
| ↑ | AP1 | electrical accumulators | ≈ 621.3824 |
| ↑ | AP3 | sensors and electric actuators | ≈ 621.3824 |
| ↑ | AP4 | congresses (electrical devices) | ≈ 621.31 |
| AV | various applications (electr.) | ≈ 621.3 |
| BI | (electronics) | ≈ 621.3 |
| CE | electromechanical constructions | ≈ 621.3 |
| ↑ | CE1 | power stations | ≈ 621.31 |
| ↑ | CE2 | wind power plants | ≈ 621.31 |
| ↑ | CE3 | hydroelectric power stations | ≈ 621.31 |
| ↑ | CE4 | nuclear power plants | ≈ 621.31 |
| ↑ | CE5 | solar power plants | ≈ 621.31 |
| ↑ | CE6 | thermoelectric power plants | ≈ 621.31 |
| CT | catalogs (elect.) | ≈ 621.3 |
| DE | electronic devices | ≈ 621.38 |
| ↑ | EE1 | planning of energy production | ≈ 621.31 |
| ↑ | EE3 | energy pricing | ≈ 621.31 |
| ↑ | EE4 | congresses (el. energy) | ≈ 621.31 |
| EG | general electronics | ≈ 621.38 |
| ↑ | EL1 | electronical CAD | ≈ 621.3815 |
| ↑ | EL10 | power electronics | ≈ 621.38 |
| ↑ | EL11 | general electronics | ≈ 621.38 |
| ↑ | EL12 | industrial electronics | ≈ 621.38 |
| ↑ | EL13 | numerical electronics | ≈ 621.38 |
| ↑ | EL14 | microelectronics | ≈ 621.3817 |
| ↑ | EL15 | neural grids | ≈ 621.38 |
| ↑ | EL16 | electronic technologies | ≈ 621.38 |
| ↑ | EL17 | VLSI | ≈ 621.38 |
| ↑ | EL18 | congresses (circuit el.) | ≈ 621.38 |
| ↑ | EL2 | analog circuits | ≈ 621.3815 |
| ↑ | EL3 | digital circuits | ≈ 621.3815 |
| ↑ | EL4 | telecommunication circuits | ≈ 621.3815 |
| ↑ | EL5 | semiconductor devices | ≈ 621.3815 |
| ↑ | EL6 | electronic circuits and devices | ≈ 621.3815 |
| ↑ | EL7 | power electronic devices | ≈ 621.3815 |
| ↑ | EL8 | organic electronics | ≈ 621.38 |
| ↑ | EL9 | civil electronics | ≈ 621.38 |
| EP | power electronics | ≈ 621.38 |
| EQ | quantum electronics | ≈ 621.38 |
| ET | general electrical engineering | ≈ 621.31 |
| ↑ | ET1 | electrical CAD | ≈ 621.31 |
| ↑ | ET10 | plasmas | ≈ 621.31 530.44 |
| ↑ | ET13 | congresses (electronics) | ≈ 621.31 |
| ↑ | ET2 | electric and magnetic fields | ≈ 621.31 |
| ↑ | ET3 | linear and non-linear electric circuits | ≈ 621.31 |
| ↑ | ET4 | electromagnetic compatibility for industrial engineering | ≈ 621.31 |
| ↑ | ET5 | general electrical engineering | ≈ 621.31 |
| ↑ | ET7 | numerical methods for electrical engineering | ≈ 519.4 621.3 |
| ↑ | ET8 | design methods for electromechanical components | ≈ 621.31 |
| ↑ | ET9 | modeling of electromechanical systems | ≈ 621.31 |
| GA | guides, anniversaries and upgrade courses (elect.) | ≈ 621.3 |
| ↑ | IE3 | illuminating engineering | ≈ 621.32 |
| IP | Production plants | ≈ 621.31 |
| LG | Electronics, information technology, electrical engineering | ≈ 621.31 |
| MA | Materials for the electronics | ≈ 621.38 |
| ME | Electrical machines | ≈ 621.3 |
| ↑ | ME1 | electric drives | ≈ 621.3 |
| ↑ | ME2 | Drives for electric traction | ≈ 621.3 |
| ↑ | ME3 | Control and regulation of electrical machines | ≈ 621.3 |
| ↑ | ME4 | Electrical machines | ≈ 621.3 |
| ↑ | ME5 | Special electric machines | ≈ 621.3 |
| ↑ | ME6 | Small electric machines | ≈ 621.3 |
| ↑ | ME7 | Congresses (Electrical machines and drives) | ≈ 621.3 |
| MI | Models and identification | ≈ 621.3 |
| MN | Manuals (Elettr.) | ≈ 621.38 |
| ↑ | MN13 | Manuals for the electronics | ≈ 621.38 |
| MO | Microwave | ≈ 621.3813 |
| ↑ | MO5 | Sensors, transducers, actuators, detectors | ≈ 621.3 |
| MP | Microprocessor | ≈ 621.3817 |
| MS | Electrical measurement | ≈ 621.3 |
| ↑ | MS1 | Electrical measuremenT | ≈ 621.3 |
| ↑ | MS2 | Electronic measures | ≈ 621.3 |
| ↑ | OE3 | Industrial and medical applications of electromagnetic waves | ≈ 621.38 |
| ↑ | OE5 | Electromagnetic compatibility | ≈ 621.38 |
| ↑ | OE7 | Numerical and CAD methods in electromagnetism | ≈ 621.38 |
| ↑ | OE8 | Microwaves, millimeter and submillimetre | ≈ 621.3813 |
| ↑ | OE9 | Electromagnetic waves and plasmas | ≈ 621.38 530.44 |
| OT | Optical | ≈ 621.36 |
| ↑ | OT1 | Industrial applications of Fourier | ≈ 621.36 |
| ↑ | OT10 | Spectroscopy | ≈ 621.36 |
| ↑ | OT11 | Congresses (Optics) | ≈ 621.36 |
| ↑ | OT2 | Quantum electronics | ≈ 621.36 |
| ↑ | OT4 | Holographic and optics of Fourier | ≈ 621.36 |
| ↑ | OT5 | General optics, optical components and instruments | ≈ 621.36 |
| ↑ | OT6 | Non linear optics | ≈ 621.36 |
| ↑ | OT7 | Quantum Optics | ≈ 621.36 |
| ↑ | OT8 | Light propagation and diffusion | ≈ 621.36 |
| RL | Logic networks | ≈ 621.38 |
| ↑ | TA1 | high tension generators | ≈ 621.31 |
| ↑ | TA2 | methods of measures in hight tension | ≈ 621.31 |
| ↑ | TA3 | congresses (high tension technique | ≈ 621.31 |
| ↑ | TE1 | telecommunications satellites | ≈ 621.382 |
| ↑ | TE10 | congresses (telecommunications) | ≈ 621.382 |
| ↑ | TE2 | radio communication systems | ≈ 621.382 |
| ↑ | TE3 | radar systems and radio aids | ≈ 621.382 |
| ↑ | TE4 | telecommunications networks, commutation | ≈ 621.382 |
| ↑ | TE5 | optical telecommunications | ≈ 621.382 |
| ↑ | TE6 | signals and noise theory | ≈ 621.39 |
| ↑ | TE7 | information theory, codes, signals processing | ≈ 621.39 |
| ↑ | TE8 | general books of electrical communications | ≈ 621.3 |
| ↑ | TE9 | transducers for telecommunications | ≈ 621.382 |
| ↑ | TL-E | thesis (electr.) | ≈ 621.3 |
| ↑ | TL-IE | thesis (electr.) | ≈ 621.3 |
| ↑ | TL-IS | thesis (electr.) | ≈ 621.3 |
| VA | electronics, computer science, electrotechnics | ≈ 621.3 |
| ↑ | VA1 | yearbooks (various) | ≈ 621.3 |
| ↑ | VA10 | various texts | ≈ 621.3 |
| ↑ | VA3 | various | ≈ 621.3 |
| VL | VLSI (large-scale integration) | ≈ 621.3815 |
