It is narrated from Sayyiduna Ibn Umar (may Allah be pleased with them both) that during the blessed era of the Noble Prophet (peace and blessings be upon him), men and women used to perform ablution together from the same vessel and would begin together.
Hadith Referenceمسند احمد / مسند المكثرين من الصحابة / 6283
Hadith Gradingحکم دارالسلام:حديث صحيح، وهذا الإسناد ظاهرة الإرسال، وقد سلف بأسانيد متصلة برقم: 4481 و 5799 و 5928 .