Yosef Karo, Shulchan Aruch — Yoreh Deah 264
“ But if there is an adult male Jew that knows how to perform circumcision he gets presidence over them all. And there are those who say that a woman does not circumcise סמק והנהות מרדכי and this is our custom to beautify with a male but an Idol worshipper even if he is circumcised, the circumcision is not a circumcision. And if he did do the circumcision we don't require returning to do a second circumcision. ”
