| ↑ | A I | history of architecture |    ≈ 720.92724 |    | 
| ↑ | A V | architectural composition |    ≈ 729.1 |    | 
|  | A.1 | Ophthalmology |  | 
|  | A.1 | Bibliographic introductions, bibliographies, library catalogues |  | 
| ↑ | A.10 | Manuals |    →        ≈    |    | 
| ↑ | A.11 | essays |    →        ≈    |    | 
|  | A.2 | Pediatric ophthalmology |  | 
|  | A.2 | Encyclopaedias and encyclopedic dictionaries |  | 
|  | A.3 | biographies |  | 
|  | A.4 | Dictionaries, vocabulary |  | 
|  | A.5 | conference proceedings |  | 
|  | A.6 | exhibitions catalogues |  | 
| ↑ | A.7a | studies in onor of |    →        ≈    |    | 
| ↑ | A.7b | scripta minora |    →        ≈    |    | 
|  | A.8 | chronology |  | 
| ↑ | A.9  |  |    →        ≈    |    | 
| ↑ | A.AR.CL.1 | Bibliographic introductions, bibliographies, library catalogues |    →        ≈    |    | 
| ↑ | A.AR.CL.10 | Excavations, topography, cartography, archaeological sites |    →        ≈    |    | 
| ↑ | A.AR.CL.10a | Excavations, topography, archaeological sites of ATHENS |    →        ≈    |    | 
| ↑ | A.AR.CL.10b | Excavations, topography, archaeological sites of ITALY |    →        ≈    |    | 
| ↑ | A.AR.CL.10c | Excavations, topography, archaeological sites |    →        ≈    |    | 
| ↑ | A.AR.CL.10d | Edizioni di scavi, topografia, siti archeologici: |    →        ≈    |    | 
| ↑ | A.AR.CL.11 | manuals |    →        ≈    |    | 
| ↑ | A.AR.CL.12 | history of archaeology |    →        ≈    |    | 
| ↑ | A.AR.CL.13 | auxiliary sciences |    →        ≈    |    | 
| ↑ | A.AR.CL.14 | Tests of a general or transverse nature |    →        ≈    |    | 
| ↑ | A.AR.CL.14a | greek archaeology |    →        ≈    |    | 
| ↑ | A.AR.CL.14b | roman archaeology |    →        ≈    |    | 
| ↑ | A.AR.CL.14c | late antiquity archeaology |    →        ≈    |    | 
| ↑ | A.AR.CL.15 | Architecture (in general) |    →        ≈    |    | 
| ↑ | A.AR.CL.15a | Greece |    →        ≈    |    | 
| ↑ | A.AR.CL.15b | Rome |    →        ≈    |    | 
| ↑ | A.AR.CL.15c | Roman provinces |    →        ≈    |    | 
| ↑ | A.AR.CL.16 | sculpture (in general) |    →        ≈    |    | 
| ↑ | A.AR.CL.16a | greek |    →        ≈    |    | 
| ↑ | A.AR.CL.16b | roman |    →        ≈    |    | 
| ↑ | A.AR.CL.16c | portraiture |    →        ≈    |    | 
| ↑ | A.AR.CL.17 | Painting (in general) |    →        ≈    |    | 
| ↑ | A.AR.CL.17a | vascular painting , painted ceramics |    →        ≈    |    | 
| ↑ | A.AR.CL.17b | painting (other classes) |    →        ≈    |    | 
| ↑ | A.AR.CL.17c | portraiture |    →        ≈    |    | 
| ↑ | A.AR.CL.17d | mosaic |    →        ≈    |    | 
| ↑ | A.AR.CL.18 | arts minor (in general) |    →        ≈    |    | 
| ↑ | A.AR.CL.18a | not painted ceramic |    →        ≈    |    | 
| ↑ | A.AR.CL.18b | metaltechnical |    →        ≈    |    | 
| ↑ | A.AR.CL.18c | jewellery |    →        ≈    |    | 
| ↑ | A.AR.CL.18d | glyptic |    →        ≈    |    | 
| ↑ | A.AR.CL.18e | glass |    →        ≈    |    | 
| ↑ | A.AR.CL.18f | forniture |    →        ≈    |    | 
| ↑ | A.AR.CL.2 | Encyclopaedias and encyclopedic dictionaries |    →        ≈    |    | 
| ↑ | A.AR.CL.3 | biographies |    →        ≈    |    | 
| ↑ | A.AR.CL.4 | dictionary, vocabulary |    →        ≈    |    | 
| ↑ | A.AR.CL.5 | conference proceedings: |    →        ≈    |    | 
| ↑ | A.AR.CL.6 | exhibitions catalogues |    →        ≈    |    | 
| ↑ | A.AR.CL.7 | Catalogues and guides of collections, museums |    →        ≈    |    | 
| ↑ | A.AR.CL.7a | sculpture |    →        ≈    |    | 
| ↑ | A.AR.CL.7b | painting |    →        ≈    |    | 
| ↑ | A.AR.CL.7c | Arts minor |    →        ≈    |    | 
| ↑ | A.AR.CL.8 | iconography |    →        ≈    |    | 
| ↑ | A.AR.CL.9 | Sources (collections or corpora of materials) |    →        ≈    |    | 
| ↑ | A.AR.CL.9a | written sources |    →        ≈    |    | 
| ↑ | A.Epigr.1 | Bibliographic introductions, bibliographies, library catalogues |    →        ≈    |    | 
| ↑ | A.Epigr.10 | manuals |    →        ≈    |    | 
| ↑ | A.Epigr.11 | essays |    →        ≈    |    | 
| ↑ | A.Epigr.2 | Encyclopaedias and encyclopedic dictionaries |    →        ≈    |    | 
| ↑ | A.Epigr.3 | biographies |    →        ≈    |    | 
| ↑ | A.Epigr.4 | dictionary, vocabulary |    →        ≈    |    | 
| ↑ | A.Epigr.5 | conference proceedings |    →        ≈    |    | 
| ↑ | A.Epigr.6 | exhibition catalogues |    →        ≈    |    | 
| ↑ | A.Epigr.7 | Catalogues and guides of lapidaries |    →        ≈    |    | 
| ↑ | A.Epigr.8 | Corpora and epigraphic syllogists |    →        ≈    |    | 
| ↑ | A.Epigr.8a | greek |    →        ≈    |    | 
| ↑ | A.Epigr.8b | Etruscan and Italic |    →        ≈    |    | 
| ↑ | A.Epigr.8c | latin |    →        ≈    |    | 
| ↑ | A.Epigr.8d | christians |    →        ≈    |    | 
| ↑ | A.Epigr.9 | Studies of epigraphy (in general) |    →        ≈    |    | 
| ↑ | A.Epigr.9a | Greece |    →        ≈    |    | 
| ↑ | A.Epigr.9b | Balkans and Eastern Europe |    →        ≈    |    | 
| ↑ | A.Epigr.9c | Etruria and pre-Roman Italy |    →        ≈    |    | 
| ↑ | A.Epigr.9d | roman italy |    →        ≈    |    | 
| ↑ | A.Epigr.9e | central and western Europe |    →        ≈    |    | 
| ↑ | A.Epigr.9f | Africa |    →        ≈    |    | 
| ↑ | A.Epigr.9g | Asia minor |    →        ≈    |    | 
| ↑ | A.Epigr.9h | Christian epigraphy |    →        ≈    |    | 
| ↑ | A.ETR.1 | Bibliographic introductions, bibliographies, library catalogues |    →        ≈    |    | 
| ↑ | A.ETR.10 | manuals |    →        ≈    |    | 
| ↑ | A.ETR.11 | Etruscan language [hermeneutics and translation/commentary essays |    →        ≈    |    | 
| ↑ | A.ETR.12 | Essays in general |    →        ≈    |    | 
| ↑ | A.ETR.12a | Essays of Architecture |    →        ≈    |    | 
| ↑ | A.ETR.12b | Essays on sculpture |    →        ≈    |    | 
| ↑ | A.ETR.12c | Essays on painting |    →        ≈    |    | 
| ↑ | A.ETR.12d | Essays on other arts (urns, sarcophagi, votive statues, etc.) |    →        ≈    |    | 
| ↑ | A.ETR.13 | Pre-roman Italy |    →        ≈    |    | 
| ↑ | A.ETR.2 | Encyclopaedias and encyclopedic dictionaries |    →        ≈    |    | 
| ↑ | A.ETR.3 | biographies |    →        ≈    |    | 
| ↑ | A.ETR.4 | dictionary, vocabulary |    →        ≈    |    | 
| ↑ | A.ETR.5 | conference proceedings |    →        ≈    |    | 
| ↑ | A.ETR.6 | exhibition catalogues |    →        ≈    |    | 
| ↑ | A.ETR.7 | Catalogues and guides of collections, museums |    →        ≈    |    | 
| ↑ | A.ETR.8 | Excavations, topography, archaeological sites |    →        ≈    |    | 
| ↑ | A.ETR.9 | literary sources |    →        ≈    |    | 
| ↑ | A.ETR.9a | Non-literary sources in collections or corpora |    →        ≈    |    | 
| ↑ | A.Or.1 | Bibliographic introductions, bibliographies, library catalogues |    →        ≈    |    | 
| ↑ | A.Or.10 | General or transverse essays |    →        ≈    |    | 
| ↑ | A.Or.11 | Assirology - Monographs |    →        ≈    |    | 
| ↑ | A.Or.12 | assirology - monographs in series |    →        ≈    |    | 
| ↑ | A.Or.13 | History of the Ancient Near East |    →        ≈    |    | 
| ↑ | A.Or.13a | History of Mesopotamian Religions, Mesopotamian Mythology |    →        ≈    |    | 
| ↑ | A.Or.14 | Anatolian civilization (in general - Hittites, Persians) |    →        ≈    |    | 
| ↑ | A.Or.14a | Historical-cultural studies , religion |    →        ≈    |    | 
| ↑ | A.Or.14b | Linguistic and Grammatical Studies, Texts |    →        ≈    |    | 
| ↑ | A.Or.14c | Anatolian hieroglyphic |    →        ≈    |    | 
| ↑ | A.Or.14d | Iron Age: First millennium a. C |    →        ≈    |    | 
| ↑ | A.Or.15 | Anatolian civilization |    →        ≈    |    | 
| ↑ | A.Or.16 | Civilization of Syria and the Levant |    →        ≈    |    | 
| ↑ | A.Or.17 | Civilization of Syria and the Levant |    →        ≈    |    | 
| ↑ | A.Or.18 | Archaeology of the Near East (in general) |    →        ≈    |    | 
| ↑ | A.Or.18a | Archaeology of Mesopotamia, Syria |    →        ≈    |    | 
| ↑ | A.Or.18b | Glittic (also includes seals) |    →        ≈    |    | 
| ↑ | A.Or.18c | Anatolian archaeology |    →        ≈    |    | 
| ↑ | A.Or.2 | Encyclopedias and encyclopedic dictionaries , Historical Atlases |    →        ≈    |    | 
| ↑ | A.Or.3 | biographies |    →        ≈    |    | 
| ↑ | A.Or.4 | dictionary, vocabulary |    →        ≈    |    | 
| ↑ | A.Or.5 | conference proceedings |    →        ≈    |    | 
| ↑ | A.Or.6 | exhibition catalogues |    →        ≈    |    | 
| ↑ | A.Or.7 | Catalogues and guides of collections, museums |    →        ≈    |    | 
| ↑ | A.Or.8 | Editions of excavations, topography |    →        ≈    |    | 
| ↑ | A.Or.9 | manuals |    →        ≈    |    | 
| ↑ | A.Or.9a | Didactic manuals (textbooks) |    →        ≈    |    | 
| ↑ | A.Or.9b | various manuals |    →        ≈    |    | 
| ↑ | A.Or.9c | grammars |    →        ≈    |    | 
| ↑ | A.Pr.1 | Bibliographic introductions, bibliographies, library catalogues |    →        ≈    |    | 
| ↑ | A.Pr.10 | prehistory and protohistory |    →        ≈    |    | 
| ↑ | A.Pr.2 | Encyclopedias and encyclopedic dictionaries |    →        ≈    |    | 
| ↑ | A.Pr.3 | biographies |    →        ≈    |    | 
| ↑ | A.Pr.4 | dictionary, vocabulary |    →        ≈    |    | 
| ↑ | A.Pr.5 | conference proceedings |    →        ≈    |    | 
| ↑ | A.Pr.6 | exhibition catalogues |    →        ≈    |    | 
| ↑ | A.Pr.7 | catalogues and guides of collections,museums |    →        ≈    |    | 
| ↑ | A.Pr.8 | manuals |    →        ≈    |    | 
| ↑ | A.Pr.9 | Essays of a general nature |    →        ≈    |    | 
| ↑ | A.Pr.9a | Prehistory and protohistory: other civilizations (not italic) |    →        ≈   |    | 
| ↑ | A.Pr.9b | Italian prehistory and protohistory. |    →        ≈    |    | 
| ↑ | A.SEM.1 | Bibliographic introductions, bibliographies |    →        ≈    |    | 
| ↑ | A.SEM.10 | manuals |    →        ≈    |    | 
| ↑ | A.SEM.10a | Grammars , books on a writing history |    →        ≈    |    | 
| ↑ | A.SEM.11 | History of Modern Judaism |    →        ≈    |    | 
| ↑ | A.SEM.11a | texts |    →        ≈    |    | 
| ↑ | A.SEM.11b | biblical exegesis , history of exegesis , biblical philology |    →        ≈    |    | 
| ↑ | A.SEM.12 | Qumran : texts and studies , Essenes |    →        ≈    |    | 
| ↑ | A.SEM.12a | Qumran : series, Sources |    →        ≈    |    | 
| ↑ | A.SEM.13 | Aramaic and Syriac: texts and studies (also place here Mandaico, Kanaaische..) |    →        ≈    |    | 
| ↑ | A.SEM.14 | Arabic and Islamic literature: texts and studies |    →        ≈    |    | 
| ↑ | A.SEM.15 | Ethiopian and related: texts and studies (includes: Amharic, Tigrinya, ge'ez..) |    →        ≈    |    | 
| ↑ | A.SEM.16 | Judaeo-Arabic literature and medieval Judaism |    →        ≈    |    | 
| ↑ | A.SEM.17 | Coptic Gnostic literature: texts and studies |    →        ≈    |    | 
| ↑ | A.SEM.18 | Storia dell'ebraismo antico: storia/geografia di Israele e della Palestina, |    →        ≈    |    | 
| ↑ | A.SEM.2 | Encyclopaedias and encyclopedic dictionaries |    →        ≈    |    | 
| ↑ | A.SEM.3 | biographies |    →        ≈    |    | 
| ↑ | A.SEM.4 | dictionary,vocabulary |    →        ≈    |    | 
| ↑ | A.SEM.5 | conference proceedings |    →        ≈    |    | 
| ↑ | A.SEM.6 | exhibition catalogues |    →        ≈    |    | 
| ↑ | A.SEM.7 | Catalogues and guides of collections, museums |    →        ≈    |    | 
| ↑ | A.SEM.8 | archeology |    →        ≈    |    | 
| ↑ | A.SEM.9 | sources |    →        ≈    |    | 
| ↑ | A.SEM.9a | series |    →        ≈    |    | 
| ↑ | A.St.A.1 | Bibliographic introductions, bibliographies, library catalogues |    →        ≈    |    | 
| ↑ | A.St.A.10 | volumes in collections |    →        ≈    |    | 
| ↑ | A.St.A.11 | History of historiography (in general) |    →        ≈    |    | 
| ↑ | A.St.A.11a | ancient historians, ethnographers and geographers |    →        ≈    |    | 
| ↑ | A.St.A.11b | modern historians |    →        ≈    |    | 
| ↑ | A.St.A.12 | manuals (in general) |    →        ≈    |    | 
| ↑ | A.St.A.13 | Essays (in general) |    →        ≈    |    | 
| ↑ | A.St.A.13a | Greek antiquities |    →        ≈    |    | 
| ↑ | A.St.A.13b | Roman antiquities |    →        ≈    |    | 
| ↑ | A.St.A.13c | agriculture , agronomy |    →        ≈    |    | 
| ↑ | A.St.A.13d | economic and social institutions |    →        ≈    |    | 
| ↑ | A.St.A.13e | demography (history of population, migratory movements, etc.) |    →        ≈    |    | 
| ↑ | A.St.A.13f | political and legal institutions |    →        ≈    |    | 
| ↑ | A.St.A.13g | geography, topography of the ancient world |    →        ≈    |    | 
| ↑ | A.St.A.13h | militaria, navalia |    →        ≈    |    | 
| ↑ | A.St.A.13i | science (in general) |    →        ≈    |    | 
| ↑ | A.St.A.13l | astronomy and mathematics |    →        ≈    |    | 
| ↑ | A.St.A.13m | natural sciences , botany |    →        ≈    |    | 
| ↑ | A.St.A.13n | medicine |    →        ≈    |    | 
| ↑ | A.St.A.13o | technologies |    →        ≈    |    | 
| ↑ | A.St.A.13p | building and urban planning |    →        ≈    |    | 
| ↑ | A.St.A.14 | Oriental history (Persia and Egypt from the VII to the IV sec. a.c.) |    →        ≈    |    | 
| ↑ | A.St.A.15 | Greek history (in general) |    →        ≈    |    | 
| ↑ | A.St.A.15a | Ancient Greece (Aegean civilization: Minoans and Mycenaeans |    →        ≈    |    | 
| ↑ | A.St.A.15b | classical Greek |    →        ≈    |    | 
| ↑ | A.St.A.15c | hellenistic word |    →        ≈    |    | 
| ↑ | A.St.A.16 | Roman history (in general) |    →        ≈    |    | 
| ↑ | A.St.A.16a | history of Rome regia |    →        ≈    |    | 
| ↑ | A.St.A.16b | history of high- and middle-republican Rome |    →        ≈    |    | 
| ↑ | A.St.A.16c | history of late Republican Rome |    →        ≈    |    | 
| ↑ | A.St.A.16d | history of imperial Rome |    →        ≈    |    | 
| ↑ | A.St.A.16e | history of the provinces of the Roman Empire |    →        ≈    |    | 
| ↑ | A.St.A.17 | Byzantine history, |    →        ≈    |    | 
| ↑ | A.St.A.18 | History of Ancient Religions (in general) |    →        ≈    |    | 
| ↑ | A.St.A.18a | primal |    →        ≈    |    | 
| ↑ | A.St.A.18b | oriental (in classical age) |    →        ≈    |    | 
| ↑ | A.St.A.18c | greek |    →        ≈    |    | 
| ↑ | A.St.A.18d | etruscan and italic |    →        ≈    |    | 
| ↑ | A.St.A.18e | roman |    →        ≈    |    | 
| ↑ | A.St.A.18f | primitive Christian (in the Roman imperial period) |    →        ≈    |    | 
| ↑ | A.St.A.18g | Judeo-Hellenistic |    →        ≈    |    | 
| ↑ | A.St.A.19 | papyrology |    →        ≈    |    | 
| ↑ | A.St.A.2 | Encyclopaedias and encyclopedic dictionaries |    →        ≈    |    | 
| ↑ | A.St.A.20 | History, society and culture of barbarian peoples, history of invasions |    →        ≈    |    | 
| ↑ | A.St.A.3 | biographies |    →        ≈    |    | 
| ↑ | A.St.A.4 | Dictionaries, lexicons |    →        ≈    |    | 
| ↑ | A.St.A.5 | Acts of congresses |    →        ≈    |    | 
| ↑ | A.St.A.6 | exhibition catalogues |    →        ≈    |    | 
| ↑ | A.St.A.7 | cronolgies |    →        ≈    |    | 
| ↑ | A.St.A.8 | Historical atlases and aerial photographs |    →        ≈    |    | 
| ↑ | A.St.A.9 | Sources not in necklace |    →        ≈    |    | 
| ↑ | A.St.A.9a | Sources in necklace |    →        ≈    |    | 
| ↑ | A11 | AGARD |    ≈ 624.17 |    | 
|  | AC | congressional acts (elect.) |  | 
| ↑ | ACF | aqueducts and sewers |    ≈ 628 |    | 
| ↑ | ACU | acoustics |    ≈ 620.2 |    | 
|  | AD | application of computers to teaching |  | 
|  | AF | reliability |  | 
| ↑ | AF1 | reliability |    ≈ 363.1620.11 |    | 
| ↑ | AF2 | reliability of the equipment and electronic systems |    ≈ 620.11621.38 |    | 
| ↑ | AF3 | reliability of electrical systems |    ≈ 620.11621317 |    | 
| ↑ | AF4 | reliability and quality control |    ≈ 620.11658.4 |    | 
| ↑ | AF5 | burn-in |    ≈ 620.11 |    | 
| ↑ | AF6 | reliability tests |    ≈ 620.11 |    | 
| ↑ | AF7 | congresses (electr. reliability) |    ≈ 620.11621.31 |    | 
|  | AI | artificial intelligence |  | 
| ↑ | AI1 | artificially intelligent |    ≈ 006.3 |    | 
| ↑ | AI2 | artificial intelligence |    ≈ 006.3 |    | 
| ↑ | AI3 | artificial intelligence 3 |    ≈ 006.3 |    | 
| ↑ | AI4 | artificial intelligence 4 |    ≈ 006.3 |    | 
| ↑ | AI5 | artificial intelligence 5 |    ≈ 006.3 |    | 
| ↑ | AI6 | artificial intelligence 6 |    ≈ 006.3 |    | 
| ↑ | AI7 | artificial intelligence 7, robotic |    ≈ 006.3629.8 |    | 
| ↑ | AI8 | artificial intelligence 8 |    ≈ 006.3 |    | 
| ↑ | AI9 | Artificial intelligence 9, image processing |    ≈ 006.3152 |    | 
| ↑ | AII | theory of architecture |    ≈ 720.1 |    | 
| ↑ | AIII | architectural composition |    ≈ 720729 |    | 
| ↑ | AIV | energetic |    ≈ 333.7720.47 |    | 
|  | AL | algebra |  | 
| ↑ | AL1 | algebra 1 |    ≈ 512 |    | 
|  | AM |  |  | 
| ↑ | AM1 | agricolture |    ≈ 333.7630 |    | 
| ↑ | AM2 | enviromnet |    ≈ 333.72720.47 |    | 
| ↑ | AM3 | quarries |    ≈ 344622.2 |    | 
| ↑ | AM4 | landfills |    ≈ 628.4 |    | 
| ↑ | AM5 | parks and nature reserve |    ≈ 719 |    | 
| ↑ | AM6 | green design |    ≈ 712 |    | 
| ↑ | AM7 | nature conservation |    ≈ 344 |    | 
| ↑ | AM8 | congresses (environment) |    ≈ 363.7 |    | 
| ↑ | AMB | environments, energy |    ≈ 333.7 |    | 
|  | AN | algorithms and numerical methods |  | 
| ↑ | AN1 | optimization algorithms |    ≈ 519 |    | 
| ↑ | AN2 | numerical analysis |    ≈ 519.4 |    | 
| ↑ | AN3 | approximation methods |    ≈ 519.4 |    | 
| ↑ | AN4 | numerical methods for partial derivative equations |    ≈ 519.4 |    | 
| ↑ | AN5 | numerical methods for ordinary differential equations |    ≈ 519.4 |    | 
| ↑ | AN6 | congresses (numerical analysis) |    ≈ 519.4 |    | 
| ↑ | ANTICO.P | old materials |   |    | 
|  | AP | aerial and propagation |  | 
| ↑ | AP1 | electrical accumulators |    ≈ 621.3824 |    | 
| ↑ | AP2 | electrical devices of manoeuvring and protection |    ≈ 621317 |    | 
| ↑ | AP3 | sensors and electric actuators |    ≈ 621.3824  |    | 
| ↑ | AP4 | congresses (electrical devices) |    ≈ 621.31 |    | 
| ↑ | APE | [energy applications (hydraulic)] |   |    | 
| ↑ | AR1 | architecture |    ≈ 720 |    | 
| ↑ | AR10 | prefabricated buildings |   |    | 
| ↑ | AR11 | residential construction |    ≈ 728 |    | 
| ↑ | AR12 | school and university buildings |    ≈ 727 |    | 
| ↑ | AR13 | sports and tourist buildings |    ≈ 725.8 |    | 
| ↑ | AR14 | parks and garden |    ≈ 712 |    | 
| ↑ | AR15 | lighting |    ≈ 729.28 |    | 
| ↑ | AR16 | fires |    ≈ 628.9 |    | 
| ↑ | AR17 | industrialization |    ≈ 658.4690.2 |    | 
| ↑ | AR18 | construction management and planning |    ≈ 658.4690.2 |    | 
| ↑ | AR19 | [design methodology] |   |    | 
| ↑ | AR2  |  |    ≈ 720.47 |    | 
| ↑ | AR20 | technical legislation |    ≈ 344 |    | 
| ↑ | AR21 | Pavia: architecture and urban planning |    ≈ 720.94529 |    | 
| ↑ | AR22 | [construction production] |   |    | 
| ↑ | AR23 | [building design] |   |    | 
| ↑ | AR24 | security of the building system |    ≈ 690.22 |    | 
| ↑ | AR25 | history of architecture and urban planning |    ≈ 722724 |    | 
| ↑ | AR26 | architecture of the twentieth century |    ≈ 724.6 |    | 
| ↑ | AR27 | architects |    ≈ 720.92 |    | 
| ↑ | AR28 | congresses (architecture) |    ≈ 720 |    | 
| ↑ | AR29 | special buildings |    ≈ 725726 |    | 
| ↑ | AR3 | Technical Architecture. |    ≈ 690721 |    | 
| ↑ | AR4 | architectural barriers. |    ≈ 720.42 |    | 
| ↑ | AR5 | Architectonic Composition |    ≈ 729.1 |    | 
| ↑ | AR6 | hospital buildings |    ≈ 725.5 |    | 
| ↑ | AR7 | building |    ≈ 690 |    | 
| ↑ | AR8 | industrial building |    ≈ 725.4 |    | 
| ↑ | AR9 | social housing |    ≈ 728.3 |    | 
| ↑ | AU1 | industrial automation |    ≈ 658.5 |    | 
| ↑ | AU2 | industrial electronics and drives |    ≈ 629 |    | 
| ↑ | AU3 | industrial robotics |    ≈ 629 |    | 
| ↑ | AU4 | Instrumentation for the automation |    ≈ 658.5 |    | 
| ↑ | AU5 | congresses (Inudstrial automation) |    ≈ 629 |    | 
|  | AV | various applications (electr.) |  | 
| ↑ | AVI | history of architecture |    ≈ 724 |    | 
|  | A_ | aereonautics |  |