Citation Rankings (Highly Cited Researchers) 2024 and list of influential and most cited researchers in Agriculture and Forestry, Art, Design and Architecture, Business and Management, Economics and Econometrics, Education, Engineering and Technology, History, Philosophy, Theology, Law, Medicine and Health Sciences, Natural Sciences and Social Sciences and their 256 sub-branches is a unique service offered only by “AD Scientific Index”. You can see the most cited and influential researchers in the country and region. See also for more specific citation analyses: "last 6 years citation index" Universities Rankings 2024 (Sort by: Total Citations) and Universities Rankings 2024 (Sort by : Last 6 Years Citations)
* Total Citation Counts Rankings
World Rank
903,134
Country Rank
887
Institution Rank : 6
![](https://cdn.adscientificindex.com/logos/11203.png)
![Bulgaria](/flags/bg.png)
![Alexander Zdravkov](/pictures/53/906107.jpg)
Coal geology and petrology
Organic and inorganic geochemistry
Source rocks
Sedimentology
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
501
222
0.443
* Total Citation Counts Rankings
World Rank
1,703,727
Country Rank
2,817
Institution Rank : 29
![](https://cdn.adscientificindex.com/logos/11203.png)
![Bulgaria](/flags/bg.png)
![Христо Димитров](/user/assets/images/profile/no-profile-photo.png)
Petroleum geology
Seismic stratigraphy
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
39
20
0.513
* Total Citation Counts Rankings
World Rank
2,015,250
Country Rank
3,664
Institution Rank : 42
![](https://cdn.adscientificindex.com/logos/11203.png)
![Bulgaria](/flags/bg.png)
![Gergana Meracheva](/user/assets/images/profile/no-profile-photo.png)
Petroleum Geology and Geochemistry
3D Geological Modelling
Petroleum System Modelling
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
9
9
1.000
* Total Citation Counts Rankings
World Ranking
903,134
Country Ranking
887
Institution Ranking
6
Alexander Zdravkov
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
501
222
0.443
![](https://cdn.adscientificindex.com/logos/11203.png)
Coal geology and petrology
Organic and inorganic geochemistry
Source rocks
Sedimentology
* Total Citation Counts Rankings
World Ranking
1,703,727
Country Ranking
2,817
Institution Ranking
29
Христо Димитров
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
39
20
0.513
![](https://cdn.adscientificindex.com/logos/11203.png)
Petroleum geology
Seismic stratigraphy
* Total Citation Counts Rankings
World Ranking
2,015,250
Country Ranking
3,664
Institution Ranking
42
Gergana Meracheva
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
9
9
1.000
![](https://cdn.adscientificindex.com/logos/11203.png)
Petroleum Geology and Geochemistry
3D Geological Modelling
Petroleum System Modelling