Citation Rankings
Highly Cited Researchers

Highly Cited Researchers 209 Scientists Citation Rankings - 2025

The Citation Rankings (Highly Cited Researchers) list highlight the most cited and influential researchers across a vast range of scientific fields, covering 197 main and sub-disciplines, including the Art and Humanities Citation Rankings and Social Sciences and Humanities Citation Rankings. This service, offered exclusively by AD Scientific Index, aims to provide a balanced perspective by excluding data from CERN and other statistical sources that disproportionately favor certain researchers, particularly in the social sciences and humanities. This unique approach addresses the advantages researchers with multi-author publications and CERN involvement hold over others. Furthermore, citation rankings help uncover rule violations and unethical practices within the research community. For more detailed citation analyses, explore the Scientists Last 6 Years Citation Index, Universities Total Citations Rankings 2025, and Universities Last 6 Years Citations Rankings 2025.

* Total Citation Counts Rankings
Ranking Based On Selection: 1
Bulgaria
Todor Popov
allergology
asthma
COPD
clinical immunology
urticaria
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
24,734
8,303
0.336
* Total Citation Counts Rankings
Ranking Based On Selection: 2
Bulgaria
Sena Karachanak-Yankova
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
19,729
11,656
0.591
* Total Citation Counts Rankings
Ranking Based On Selection: 3
Bulgaria
Irini Doytchinova
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
11,351
6,294
0.554
* Total Citation Counts Rankings
Ranking Based On Selection: 4
Bulgaria
Irena Kostova
coordination chemistry
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
8,031
2,781
0.346
* Total Citation Counts Rankings
Ranking Based On Selection: 5
Bulgaria
Georgi Momekov
Anticancer agents
Phytopharmacology
Multidrug resistance
Drug interactions
Antimicrobials
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
4,658
1,940
0.416
* Total Citation Counts Rankings
Ranking Based On Selection: 6
Bulgaria
Zdravko Kamenov
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
4,406
2,344
0.532
* Total Citation Counts Rankings
Ranking Based On Selection: 7
Bulgaria
Boris Tenchov
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
4,018
741
0.184
* Total Citation Counts Rankings
Ranking Based On Selection: 8
Bulgaria
Elena Kinova
Cardiology
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
2,688
2,646
0.984
* Total Citation Counts Rankings
Ranking Based On Selection: 9
Bulgaria
Nikolai Lazarov
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
2,531
989
0.391

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* Total Citation Counts Rankings
Ranking Based On Selection: 10
Bulgaria
Georgi Onchev
culture
psychopathology
psychosis
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
1,995
707
0.354
* Total Citation Counts Rankings
Ranking Based On Selection: 11
Bulgaria
Alexander Shinkov
Endocrinology
Thyroid
Parathyroid
Metabolic bone disease
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
1,909
958
0.502
* Total Citation Counts Rankings
Ranking Based On Selection: 12
Bulgaria
Magdalena Kondeva-Burdina
Toxicology
Drug metabolism
Hepatoprotection
Neuroprotection
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
1,734
1,247
0.719
* Total Citation Counts Rankings
Ranking Based On Selection: 13
Bulgaria
Paraskev Nedialkov
pharmacognosy
phytochemistry
NMR
LC-MS
GC-MS
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
1,639
881
0.538
* Total Citation Counts Rankings
Ranking Based On Selection: 14
Bulgaria
Maria Staevska
Allergy & Clinical Immunology
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
1,420
719
0.506
* Total Citation Counts Rankings
Ranking Based On Selection: 15
Bulgaria
Irina Nikolova
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
1,242
382
0.308
* Total Citation Counts Rankings
Ranking Based On Selection: 16
Bulgaria
Ivan Lyutakov
Gastroenterology
IBD
Endoscopy
Bile acid malabsorption
Microscopic colitis
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
1,211
1,210
0.999
* Total Citation Counts Rankings
Ranking Based On Selection: 17
Bulgaria
Ekaterina Kozuharova|Kozhuharova Kohuzarova Kohazurova
Pollination Ecology
Plant Breeding Systems
Invasive plants
Ethnobotany
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
1,188
808
0.680
* Total Citation Counts Rankings
Ranking Based On Selection: 18
Bulgaria
Nikolay Ishkitiev
adult stem cells
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
1,128
408
0.362
* Total Citation Counts Rankings
Ranking Based On Selection: 19
Bulgaria
Dimitar Maslarov
neurology
neurosciences
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
1,093
861
0.788
* Total Citation Counts Rankings
Ranking Based On Selection: 20
Bulgaria
Boycho Landzhov
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
1,018
549
0.539
* Total Citation Counts Rankings
Ranking Based On Selection: 21
Bulgaria
Rumiana Simeonova
drug metabolism
drug toxicity
oxidative stress
drug interactions
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
938
615
0.656
* Total Citation Counts Rankings
Ranking Based On Selection: 22
Bulgaria
Nevena Chakarova
endocrinology
prediabetes
diabetes
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
912
596
0.654
* Total Citation Counts Rankings
Ranking Based On Selection: 23
Bulgaria
Aleksandrina Vlahova
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
834
492
0.590
* Total Citation Counts Rankings
Ranking Based On Selection: 24
Bulgaria
Aleksandar Shkondrov
natural products
saponins
flavonoids
phytochemistry
chromatography
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
703
562
0.799
* Total Citation Counts Rankings
Ranking Based On Selection: 25
Bulgaria
A Savova|Alexandra Tzenova-Savova
pharmaceutical legislation
pharmacoeconomics
HTA
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
700
439
0.627
* Total Citation Counts Rankings
Rankings
30,750
Bulgaria
11
1
Ranking Based On Selection: 1
Todor Popov
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
24,734
8,303
0.336
allergology
asthma
COPD
clinical immunology
urticaria
* Total Citation Counts Rankings
Rankings
42,253
Bulgaria
13
2
Ranking Based On Selection: 2
Sena Karachanak-Yankova
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
19,729
11,656
0.591
* Total Citation Counts Rankings
Rankings
86,749
Bulgaria
28
3
Ranking Based On Selection: 3
Irini Doytchinova
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
11,351
6,294
0.554
* Total Citation Counts Rankings
Rankings
128,745
Bulgaria
45
4
Ranking Based On Selection: 4
Irena Kostova
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
8,031
2,781
0.346
* Total Citation Counts Rankings
Rankings
223,482
Bulgaria
82
5
Ranking Based On Selection: 5
Georgi Momekov
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
4,658
1,940
0.416
Anticancer agents
Phytopharmacology
Multidrug resistance
Drug interactions
Antimicrobials
* Total Citation Counts Rankings
Rankings
235,329
Bulgaria
88
6
Ranking Based On Selection: 6
Zdravko Kamenov
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
4,406
2,344
0.532
* Total Citation Counts Rankings
Rankings
256,259
Bulgaria
98
7
Ranking Based On Selection: 7
Boris Tenchov
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
4,018
741
0.184
* Total Citation Counts Rankings
Rankings
359,131
Bulgaria
171
8
Ranking Based On Selection: 8
Elena Kinova
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
2,688
2,646
0.984
* Total Citation Counts Rankings
Rankings
376,454
Bulgaria
182
9
Ranking Based On Selection: 9
Nikolai Lazarov
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
2,531
989
0.391
* Total Citation Counts Rankings
Rankings
448,909
Bulgaria
257
10
Ranking Based On Selection: 10
Georgi Onchev
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
1,995
707
0.354

360° Institutional Performance & Benchmarking Click Here for Live Demo 

Gain data-driven strategic insights into your institution’s academic performance, global positioning, and competitive strengths through advanced analysis and benchmarking

with 20 similarly ranked institutions at City, Country, Region, and Global levels. 

* Total Citation Counts Rankings
Rankings
463,095
Bulgaria
267
11
Ranking Based On Selection: 11
Alexander Shinkov
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
1,909
958
0.502
* Total Citation Counts Rankings
Rankings
494,585
Bulgaria
299
12
Ranking Based On Selection: 12
Magdalena Kondeva-Burdina
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
1,734
1,247
0.719
* Total Citation Counts Rankings
Rankings
513,686
Bulgaria
318
13
Ranking Based On Selection: 13
Paraskev Nedialkov
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
1,639
881
0.538
* Total Citation Counts Rankings
Rankings
562,351
Bulgaria
383
14
Ranking Based On Selection: 14
Maria Staevska
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
1,420
719
0.506
* Total Citation Counts Rankings
Rankings
609,337
Bulgaria
437
15
Ranking Based On Selection: 15
Irina Nikolova
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
1,242
382
0.308
* Total Citation Counts Rankings
Rankings
618,114
Bulgaria
448
16
Ranking Based On Selection: 16
Ivan Lyutakov
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
1,211
1,210
0.999
Gastroenterology
IBD
Endoscopy
Bile acid malabsorption
Microscopic colitis
* Total Citation Counts Rankings
Rankings
625,045
Bulgaria
456
17
Ranking Based On Selection: 17
Ekaterina Kozuharova|Kozhuharova Kohuzarova Kohazurova
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
1,188
808
0.680
Pollination Ecology
Plant Breeding Systems
Invasive plants
Ethnobotany
* Total Citation Counts Rankings
Rankings
643,928
Bulgaria
478
18
Ranking Based On Selection: 18
Nikolay Ishkitiev
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
1,128
408
0.362
* Total Citation Counts Rankings
Rankings
654,920
Bulgaria
494
19
Ranking Based On Selection: 19
Dimitar Maslarov
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
1,093
861
0.788
* Total Citation Counts Rankings
Rankings
680,576
Bulgaria
529
20
Ranking Based On Selection: 20
Boycho Landzhov
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
1,018
549
0.539
* Total Citation Counts Rankings
Rankings
709,807
Bulgaria
558
21
Ranking Based On Selection: 21
Rumiana Simeonova
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
938
615
0.656
drug metabolism
drug toxicity
oxidative stress
drug interactions
* Total Citation Counts Rankings
Rankings
720,044
Bulgaria
570
22
Ranking Based On Selection: 22
Nevena Chakarova
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
912
596
0.654
* Total Citation Counts Rankings
Rankings
751,747
Bulgaria
630
23
Ranking Based On Selection: 23
Aleksandrina Vlahova
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
834
492
0.590
* Total Citation Counts Rankings
Rankings
810,795
Bulgaria
724
24
Ranking Based On Selection: 24
Aleksandar Shkondrov
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
703
562
0.799
natural products
saponins
flavonoids
phytochemistry
chromatography
* Total Citation Counts Rankings
Rankings
812,395
Bulgaria
728
25
Ranking Based On Selection: 25
A Savova|Alexandra Tzenova-Savova
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
700
439
0.627
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