There were a couple of women standing at Jesus' cross and they are mentioned at three places in the Bible. The listings are slightly different and here is how they can be reconciled: (The persons listed in the same row are the same.)

Mat 27:56	Mark 15:40	John 19:25
Mary Magdalene	Mary Magdalene	Mary Magdalene
Mary the mother of James and Joses	Mary the mother of James the less and of Joses	his mother
mother of Zebedees children
	Salome
		his mother's sister
		Mary the wife of Cleophas