Lyubomirova, V., Belovezhdova, I., Kamusheva, A., Ignatov, P. and Tuhchiev, P. (2026) “Optimization of Solid-phase Extraction and GC-MS/MS Determination of PAHs in Bulgarian Sewage Sludge”, Proceedings of the Bulgarian Academy of Sciences. Sofia, Bulgaria, 79(3), pp. 312–320. doi: 10.7546/CRABS.2026.03.04.