Puc , M., P. Rapiejko, A. Stacewicz, G. Siergiejko, E. M. Świebocka, D. Jurkiewicz, Z. Sankowski, and A. Lipiec. “Hazel Pollen in the Air of Northern Poland in 2017”. Alergoprofil, Vol. 13, no. 2, June 2017, pp. 68-71, https://www.journalsmededu.pl/index.php/alergoprofil/article/view/890.