Spontaneous resolution of pneumomediastinum in children – clinical experience - Korecka, Klaudia; Hyla-Klekot, Lidia; Kęsek, Mateusz; Kudela, Grzegorz; Bulandra, Andrzej Michał; Koszutski, Tomasz (Pediatria Polska - Polish Journal of Paediatrics, 2019)