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
Oxytetracycline Residues in Honey Analyzed by Liquid Chromatography with UV Detection
Gajda, Anna, Posyniak, Andrzej, Bober, Andrzej, Błądek, Tomasz, Żmudzki, Jan