Is it permissible to marry the daughter of a paternal male cousin's daughter, given that the questioner and his paternal male cousin (who is her maternal uncle) were nursed together in infancy?

If you suckled with the girl's maternal uncle from his mother (the girl's grandmother), you become her grandmother's son through suckling and the girl's maternal uncle through suckling. In this case, marriage to her is not permissible for you. However, if the suckling occurred from another party, it does not affect the permissibility of marriage.