| Issue Date | Title | Author(s) | Type | Мp-cat. |
| 2023 | Comparative Petrographical and Organic Geochemical Study of Eocene and Oligocene Coal Basins from Sw Bulgaria | Zdravkov, Alexander; Gross, Doris; Stojanović, Ksenija   ; Bechtel, Achim; Kojić, Ivan | Conference Paper | |
| 2023 | Depositional settings of the Eocene Suhostrel bituminous coal, SW Bulgaria, inferred from organic petrology and molecular proxies | Zdravkov, Alexander; Gross, Doris; Bechtel, Achim; Stojanovic, Ksenija A ; Kojic, Ivan D | Article | |
| 2023 | Paleoenvironmental settings of peat formation within Padesh Graben, SW Bulgaria, deduced from maceral analysis and geochemical properties of Suhostrel Coal | Zdravkov, Alexander; Gross, Doris; Bechtel, Achim; Stojanović, Ksenija ; Kojić, Ivan | Conference Paper | |
| 2024 | Paleovegetation and environment during deposition of the Late Oligocene sub-bituminous coal in the Bobov Dol Basin (SW Bulgaria) as deduced from petrographic and geochemical characteristics | Zdravkov, Alexander; Bechtel, Achim; Groβ, Doris; Kojić, Ivan ; Stojanović, Ksenija ; Životić, Dragana | Article | |
| 2025 | Petrological and organic geochemical insights into the peat-forming environmental settings during the deposition of the early Oligocene Pirin coal deposit, SW Bulgaria | Zdravkov, Alexander; Bechtel, Achim; Stojanovic, Ksenija ; Gross, Doris; Weitz, Johannes; Kojic, Ivan ; Sachsenhofer, Reinhard F; Misch, David; Zivotic, Dragana R | Article | |
| 2023 | Reconstruction of peat-forming paleoenvironments within the Oligocene Bobov Dol Basin, SW Bulgaria: Insights from organic petrology | Zdravkov, Alexander; Bechtel, Achim; Gross, Doris; Stojanović, Ksenija | Conference Paper | |