A. H. Clifford

6.2k total citations · 1 hit paper
34 papers, 3.5k citations indexed

About

A. H. Clifford is a scholar working on Computational Theory and Mathematics, Management Science and Operations Research and Geometry and Topology. According to data from OpenAlex, A. H. Clifford has authored 34 papers receiving a total of 3.5k indexed citations (citations by other indexed papers that have themselves been cited), including 29 papers in Computational Theory and Mathematics, 17 papers in Management Science and Operations Research and 8 papers in Geometry and Topology. Recurrent topics in A. H. Clifford's work include semigroups and automata theory (26 papers), Fuzzy and Soft Set Theory (17 papers) and Advanced Algebra and Logic (17 papers). A. H. Clifford is often cited by papers focused on semigroups and automata theory (26 papers), Fuzzy and Soft Set Theory (17 papers) and Advanced Algebra and Logic (17 papers). A. H. Clifford collaborates with scholars based in United States. A. H. Clifford's co-authors include G. B. Preston, Mario Petrich, Norman R. Reilly and Paul Conrad and has published in prestigious journals such as Transactions of the American Mathematical Society, Bulletin of the American Mathematical Society and Proceedings of the American Mathematical Society.

In The Last Decade

A. H. Clifford

29 papers receiving 2.7k citations

Hit Papers

The algebraic theory of semigroups 1964 2026 1984 2005 1964 500 1000 1.5k 2.0k 2.5k
What are hit papers?

Hit papers significantly outperform the citation benchmark for their cohort. A paper qualifies if it has ≥500 total citations, achieves ≥1.5× the top-1% citation threshold for papers in the same subfield and year (this is the minimum needed to enter the top 1%, not the average within it), or reaches the top citation threshold in at least one of its specific research topics.

  1. The algebraic theory of semigroups
    1964 2.6k citations A. H. Clifford, G. B. Preston CERN Document Server (European Organization for Nuclear Research) profile →

Peers — A (Enhanced Table)

Peers by citation overlap · career bar shows stage (early→late) cites · hero ref

Name h Career Trend Papers Cites
A. H. Clifford United States 15 2.9k 1.2k 928 813 471 34 3.5k
G. B. Preston United States 12 2.5k 0.9× 942 0.8× 846 0.9× 740 0.9× 446 0.9× 45 3.1k
John Howie United Kingdom 23 3.6k 1.2× 1.1k 0.9× 1.3k 1.4× 926 1.1× 529 1.1× 100 4.2k
Mario Petrich Canada 23 1.7k 0.6× 875 0.7× 328 0.4× 346 0.4× 146 0.3× 200 2.0k
Horst Herrlich Germany 22 1.4k 0.5× 864 0.7× 1.2k 1.3× 988 1.2× 1.2k 2.5× 125 3.0k
Stanley Burris Canada 17 2.9k 1.0× 694 0.6× 359 0.4× 614 0.8× 154 0.3× 72 3.2k
Andreas Blass United States 26 2.3k 0.8× 338 0.3× 945 1.0× 475 0.6× 535 1.1× 164 3.2k
Bjàrni Jónsson United States 28 1.7k 0.6× 311 0.3× 452 0.5× 683 0.8× 214 0.5× 68 2.3k
G. E. Strecker United States 11 904 0.3× 553 0.5× 466 0.5× 366 0.5× 454 1.0× 36 1.6k
Jonathan S. Golan Israel 13 701 0.2× 330 0.3× 335 0.4× 697 0.9× 126 0.3× 53 1.3k
Mark V. Lawson United Kingdom 17 977 0.3× 189 0.2× 591 0.6× 465 0.6× 555 1.2× 81 1.4k

Countries citing papers authored by A. H. Clifford

Since Specialization
Citations

This map shows the geographic impact of A. H. Clifford's research. It shows the number of citations coming from papers published by authors working in each country. You can also color the map by specialization and compare the number of citations received by A. H. Clifford with the expected number of citations based on a country's size and research output (numbers larger than one mean the country cites A. H. Clifford more than expected).

Fields of papers citing papers by A. H. Clifford

Since Specialization
Physical SciencesHealth SciencesLife SciencesSocial Sciences

This network shows the impact of papers produced by A. H. Clifford. Nodes represent research fields, and links connect fields that are likely to share authors. Colored nodes show fields that tend to cite the papers produced by A. H. Clifford. The network helps show where A. H. Clifford may publish in the future.

Co-authorship network of co-authors of A. H. Clifford

This figure shows the co-authorship network connecting the top 25 collaborators of A. H. Clifford. A scholar is included among the top collaborators of A. H. Clifford based on the total number of citations received by their joint publications. Widths of edges represent the number of papers authors have co-authored together. Node borders signify the number of papers an author published with A. H. Clifford. A. H. Clifford is excluded from the visualization to improve readability, since they are connected to all nodes in the network.

All Works

20 of 20 papers shown
1.
Clifford, A. H.. (1979). The free completely regular semigroup on a set. Semigroup Forum. 18(1). 87–91. 1 indexed citations
2.
Clifford, A. H.. (1979). The free completely regular semigroup on a set. Journal of Algebra. 59(2). 434–451. 45 indexed citations
3.
Clifford, A. H.. (1978). Remarks on 0-minimal quasi-ideals in semigroups. Semigroup Forum. 16(1). 183–196. 6 indexed citations
4.
Clifford, A. H. & Mario Petrich. (1977). Some classes of completely regular semigroups. Journal of Algebra. 46(2). 462–480. 14 indexed citations
5.
Clifford, A. H.. (1976). A structure theorem for orthogroups. Journal of Pure and Applied Algebra. 8(1). 23–50. 5 indexed citations
6.
Clifford, A. H.. (1976). The fundamental representation of a completely regular semigroup. Semigroup Forum. 12(1). 341–346. 7 indexed citations
7.
Clifford, A. H.. (1975). The partial groupoid of idempotents of a regular semigroup. Semigroup Forum. 10(1). 262–268. 12 indexed citations
8.
Clifford, A. H.. (1972). The structure of bisimple orthodox semigroups as ordered pairs. Semigroup Forum. 5(1). 127–136. 6 indexed citations
9.
Clifford, A. H., et al.. (1970). Union and symmetry preserving endomorphisms of the semigroup of all binary relations on a set. Czechoslovak Mathematical Journal. 20(2). 303–314. 16 indexed citations
10.
Clifford, A. H. & G. B. Preston. (1967). The Algebraic Theory of Semigroups, Volume II. Mathematical surveys and monographs. 208 indexed citations
11.
Clifford, A. H.. (1965). Partial homomorphic images of Brandt groupoids. Proceedings of the American Mathematical Society. 16(3). 538–544. 5 indexed citations
12.
Clifford, A. H. & G. B. Preston. (1964). The algebraic theory of semigroups. CERN Document Server (European Organization for Nuclear Research). 2593 indexed citations breakdown →
13.
Clifford, A. H.. (1963). Note on a Double Coset Decomposition of Semigroups due to Štefan Schwarz. Czech digital mathematics library. 13(1). 55–57. 1 indexed citations
14.
Conrad, Paul & A. H. Clifford. (1960). Lattice-ordered groups having at most two disjoint elements. Proceedings of the Glasgow Mathematical Association. 4(3). 111–113. 7 indexed citations
15.
Clifford, A. H.. (1958). Ordered commutative semigroups of the second kind. Proceedings of the American Mathematical Society. 9(5). 682–687. 5 indexed citations
16.
Clifford, A. H.. (1958). Connected ordered topological semigroups with idempotent endpoints. I.. Transactions of the American Mathematical Society. 88(1). 80–98. 28 indexed citations
17.
Clifford, A. H.. (1954). Naturally Totally Ordered Commutative Semigroups. American Journal of Mathematics. 76(3). 631–631. 181 indexed citations
18.
Clifford, A. H.. (1954). Bands of semigroups. Proceedings of the American Mathematical Society. 5(3). 499–504. 50 indexed citations
19.
Clifford, A. H.. (1953). A Class of d-Simple Semigroups. American Journal of Mathematics. 75(3). 547–547. 50 indexed citations
20.
Clifford, A. H.. (1951). A noncommutative ordinally simple linearly ordered group. Proceedings of the American Mathematical Society. 2(6). 902–903. 13 indexed citations

Rankless uses publication and citation data sourced from OpenAlex, an open and comprehensive bibliographic database. While OpenAlex provides broad and valuable coverage of the global research landscape, it—like all bibliographic datasets—has inherent limitations. These include incomplete records, variations in author disambiguation, differences in journal indexing, and delays in data updates. As a result, some metrics and network relationships displayed in Rankless may not fully capture the entirety of a scholar's output or impact.

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