Levels of the natural hormones 17β-oestradiol and testosterone in serum of cattle: results from population studies in Poland
Woźniak, Barbara, Witek, Sebastian, Matraszek-Żuchowska, Iwona, Kłopot, Alicja, Posyniak, Andrzej
LC-MS/MS analysis of doxycycline residues in chicken tissues after oral administration
Gajda, Anna, Posyniak, Andrzej, Tomczyk, Grzegorz