A child with chronic functional constipation – a challenge for a pediatrician alone or a surgeon as well? Case series and literature review - Dybowska, Aleksandra; Kupniewska, Paulina; Sobacka, Agata; Kroczek, Kacper; Krogulska, Aneta; Gałązka, Przemysław (Pediatria Polska - Polish Journal of Paediatrics, 2022)