Fisichella، P. Marco؛ Patti، Marco G. (أكتوبر 2014). "From Heller to POEM (1914-2014): a 100-year history of surgery for Achalasia". Journal of Gastrointestinal Surgery. ج. 18 ع. 10: 1870–1875. DOI:10.1007/s11605-014-2547-8. ISSN:1873-4626. PMID:24878993. S2CID:1290385.
Fisichella، P. Marco؛ Patti، Marco G. (أكتوبر 2014). "From Heller to POEM (1914-2014): a 100-year history of surgery for Achalasia". Journal of Gastrointestinal Surgery. ج. 18 ع. 10: 1870–1875. DOI:10.1007/s11605-014-2547-8. ISSN:1873-4626. PMID:24878993. S2CID:1290385.
Fisichella، P. Marco؛ Patti، Marco G. (أكتوبر 2014). "From Heller to POEM (1914-2014): a 100-year history of surgery for Achalasia". Journal of Gastrointestinal Surgery. ج. 18 ع. 10: 1870–1875. DOI:10.1007/s11605-014-2547-8. ISSN:1873-4626. PMID:24878993. S2CID:1290385.
Fisichella، P. Marco؛ Patti، Marco G. (أكتوبر 2014). "From Heller to POEM (1914-2014): a 100-year history of surgery for Achalasia". Journal of Gastrointestinal Surgery. ج. 18 ع. 10: 1870–1875. DOI:10.1007/s11605-014-2547-8. ISSN:1873-4626. PMID:24878993. S2CID:1290385.