2SHAFER AD, MCGLONE TP, FLANAGAN RA. Abnormal crypts of Morgagni:The cause of perianal abscess and fistula-in-ano[J]. J Pediatr Surg,1987,22(3):203-204.
3FITZGERALD RJ, HARDING B, RYAN W. Fistula-in-ano in childhood: A con2 genital etiology[J]. J Pediatr Surg, 1985,20 (1):80-81.