1. Classification of the esophageal motility disorders;Cohen S.;Gastroenterology.,1983
2. Esophageal motor dysfunction in systemic diseases;Mukhopadhyay A;Arch Intern Med.,1976
3. The Chicago Classification of esophageal motility disorders, v3.0
4. Oesophageal motility and its disorders
5. Dysfunction of Pharyngeal Swallowing