{"id":"https://openalex.org/W2054979344","doi":"https://doi.org/10.1016/0097-3165(80)90017-5","title":"On projective planes of order 12 which have a subplane of order 3, I","display_name":"On projective planes of order 12 which have a subplane of order 3, I","publication_year":1980,"publication_date":"1980-09-01","ids":{"openalex":"https://openalex.org/W2054979344","doi":"https://doi.org/10.1016/0097-3165(80)90017-5","mag":"2054979344"},"language":"en","primary_location":{"id":"doi:10.1016/0097-3165(80)90017-5","is_oa":false,"landing_page_url":"https://doi.org/10.1016/0097-3165(80)90017-5","pdf_url":null,"source":{"id":"https://openalex.org/S128556326","display_name":"Journal of Combinatorial Theory Series A","issn_l":"0097-3165","issn":["0097-3165","1096-0899"],"is_oa":false,"is_in_doaj":false,"is_core":true,"host_organization":"https://openalex.org/P4310320990","host_organization_name":"Elsevier BV","host_organization_lineage":["https://openalex.org/P4310320990"],"host_organization_lineage_names":["Elsevier BV"],"type":"journal"},"license":null,"license_id":null,"version":"publishedVersion","is_accepted":true,"is_published":true,"raw_source_name":"Journal of Combinatorial Theory, Series A","raw_type":"journal-article"},"type":"article","indexed_in":["crossref"],"open_access":{"is_oa":false,"oa_status":"closed","oa_url":null,"any_repository_has_fulltext":false},"authorships":[{"author_position":"first","author":{"id":"https://openalex.org/A5061048354","display_name":"Zvonimir Janko","orcid":null},"institutions":[{"id":"https://openalex.org/I223822909","display_name":"Heidelberg University","ror":"https://ror.org/038t36y30","country_code":"DE","type":"education","lineage":["https://openalex.org/I223822909"]}],"countries":["DE"],"is_corresponding":true,"raw_author_name":"Zvonimir Janko","raw_affiliation_strings":["Mathematisches Institut, University of Heidelberg, 6900 Heidelberg I, West Germany"],"affiliations":[{"raw_affiliation_string":"Mathematisches Institut, University of Heidelberg, 6900 Heidelberg I, West Germany","institution_ids":["https://openalex.org/I223822909"]}]},{"author_position":"last","author":{"id":"https://openalex.org/A5064571214","display_name":"Tran van Trung","orcid":"https://orcid.org/0000-0001-7453-357X"},"institutions":[{"id":"https://openalex.org/I223822909","display_name":"Heidelberg University","ror":"https://ror.org/038t36y30","country_code":"DE","type":"education","lineage":["https://openalex.org/I223822909"]}],"countries":["DE"],"is_corresponding":false,"raw_author_name":"Tran van Trung","raw_affiliation_strings":["Mathematisches Institut, University of Heidelberg, 6900 Heidelberg I, West Germany"],"affiliations":[{"raw_affiliation_string":"Mathematisches Institut, University of Heidelberg, 6900 Heidelberg I, West Germany","institution_ids":["https://openalex.org/I223822909"]}]}],"institutions":[],"countries_distinct_count":1,"institutions_distinct_count":2,"corresponding_author_ids":["https://openalex.org/A5061048354"],"corresponding_institution_ids":["https://openalex.org/I223822909"],"apc_list":{"value":3320,"currency":"USD","value_usd":3320},"apc_paid":null,"fwci":0.45561321,"has_fulltext":false,"cited_by_count":8,"citation_normalized_percentile":{"value":0.69035343,"is_in_top_1_percent":false,"is_in_top_10_percent":false},"cited_by_percentile_year":{"min":89,"max":94},"biblio":{"volume":"29","issue":"2","first_page":"254","last_page":"256"},"is_retracted":false,"is_paratext":false,"is_xpac":false,"primary_topic":{"id":"https://openalex.org/T11797","display_name":"graph theory and CDMA systems","score":0.9998000264167786,"subfield":{"id":"https://openalex.org/subfields/2208","display_name":"Electrical and Electronic Engineering"},"field":{"id":"https://openalex.org/fields/22","display_name":"Engineering"},"domain":{"id":"https://openalex.org/domains/3","display_name":"Physical Sciences"}},"topics":[{"id":"https://openalex.org/T11797","display_name":"graph theory and CDMA systems","score":0.9998000264167786,"subfield":{"id":"https://openalex.org/subfields/2208","display_name":"Electrical and Electronic Engineering"},"field":{"id":"https://openalex.org/fields/22","display_name":"Engineering"},"domain":{"id":"https://openalex.org/domains/3","display_name":"Physical Sciences"}},{"id":"https://openalex.org/T10849","display_name":"Finite Group Theory Research","score":0.9970999956130981,"subfield":{"id":"https://openalex.org/subfields/2607","display_name":"Discrete Mathematics and Combinatorics"},"field":{"id":"https://openalex.org/fields/26","display_name":"Mathematics"},"domain":{"id":"https://openalex.org/domains/3","display_name":"Physical Sciences"}},{"id":"https://openalex.org/T11130","display_name":"Coding theory and cryptography","score":0.9781000018119812,"subfield":{"id":"https://openalex.org/subfields/1702","display_name":"Artificial Intelligence"},"field":{"id":"https://openalex.org/fields/17","display_name":"Computer Science"},"domain":{"id":"https://openalex.org/domains/3","display_name":"Physical Sciences"}}],"keywords":[{"id":"https://openalex.org/keywords/order","display_name":"Order (exchange)","score":0.7027765512466431},{"id":"https://openalex.org/keywords/projective-test","display_name":"Projective test","score":0.6544052958488464},{"id":"https://openalex.org/keywords/mathematics","display_name":"Mathematics","score":0.46718719601631165},{"id":"https://openalex.org/keywords/projective-plane","display_name":"Projective plane","score":0.4218302071094513},{"id":"https://openalex.org/keywords/pure-mathematics","display_name":"Pure mathematics","score":0.3635295033454895},{"id":"https://openalex.org/keywords/geometry","display_name":"Geometry","score":0.30407679080963135},{"id":"https://openalex.org/keywords/economics","display_name":"Economics","score":0.05293327569961548}],"concepts":[{"id":"https://openalex.org/C182306322","wikidata":"https://www.wikidata.org/wiki/Q1779371","display_name":"Order (exchange)","level":2,"score":0.7027765512466431},{"id":"https://openalex.org/C177846678","wikidata":"https://www.wikidata.org/wiki/Q1501864","display_name":"Projective test","level":2,"score":0.6544052958488464},{"id":"https://openalex.org/C33923547","wikidata":"https://www.wikidata.org/wiki/Q395","display_name":"Mathematics","level":0,"score":0.46718719601631165},{"id":"https://openalex.org/C39290043","wikidata":"https://www.wikidata.org/wiki/Q1475760","display_name":"Projective plane","level":3,"score":0.4218302071094513},{"id":"https://openalex.org/C202444582","wikidata":"https://www.wikidata.org/wiki/Q837863","display_name":"Pure mathematics","level":1,"score":0.3635295033454895},{"id":"https://openalex.org/C2524010","wikidata":"https://www.wikidata.org/wiki/Q8087","display_name":"Geometry","level":1,"score":0.30407679080963135},{"id":"https://openalex.org/C162324750","wikidata":"https://www.wikidata.org/wiki/Q8134","display_name":"Economics","level":0,"score":0.05293327569961548},{"id":"https://openalex.org/C117220453","wikidata":"https://www.wikidata.org/wiki/Q5172842","display_name":"Correlation","level":2,"score":0.0},{"id":"https://openalex.org/C10138342","wikidata":"https://www.wikidata.org/wiki/Q43015","display_name":"Finance","level":1,"score":0.0}],"mesh":[],"locations_count":1,"locations":[{"id":"doi:10.1016/0097-3165(80)90017-5","is_oa":false,"landing_page_url":"https://doi.org/10.1016/0097-3165(80)90017-5","pdf_url":null,"source":{"id":"https://openalex.org/S128556326","display_name":"Journal of Combinatorial Theory Series A","issn_l":"0097-3165","issn":["0097-3165","1096-0899"],"is_oa":false,"is_in_doaj":false,"is_core":true,"host_organization":"https://openalex.org/P4310320990","host_organization_name":"Elsevier BV","host_organization_lineage":["https://openalex.org/P4310320990"],"host_organization_lineage_names":["Elsevier BV"],"type":"journal"},"license":null,"license_id":null,"version":"publishedVersion","is_accepted":true,"is_published":true,"raw_source_name":"Journal of Combinatorial Theory, Series A","raw_type":"journal-article"}],"best_oa_location":null,"sustainable_development_goals":[{"id":"https://metadata.un.org/sdg/11","display_name":"Sustainable cities and communities","score":0.6200000047683716}],"awards":[],"funders":[],"has_content":{"grobid_xml":false,"pdf":false},"content_urls":null,"referenced_works_count":2,"referenced_works":["https://openalex.org/W1534310607","https://openalex.org/W2328170380"],"related_works":["https://openalex.org/W2095350651","https://openalex.org/W2044219908","https://openalex.org/W4311864151","https://openalex.org/W2439115288","https://openalex.org/W3194074439","https://openalex.org/W2112160125","https://openalex.org/W2077442345","https://openalex.org/W4311989719","https://openalex.org/W4253046635","https://openalex.org/W2783053240"],"abstract_inverted_index":null,"counts_by_year":[{"year":2023,"cited_by_count":1},{"year":2022,"cited_by_count":1}],"updated_date":"2025-11-06T03:46:38.306776","created_date":"2025-10-10T00:00:00"}