Please answer the following question: Given the following passage  "In 1997, the Vienna Philharmonic was "facing protests during a [US] tour" by the National Organization for Women and the International Alliance for Women in Music. Finally, "after being held up to increasing ridicule even in socially conservative Austria, members of the orchestra gathered [on 28 February 1997] in an extraordinary meeting on the eve of their departure and agreed to admit a woman, Anna Lelkes, as harpist." As of 2013, the orchestra has six female members; one of them, violinist Albena Danailova became one of the orchestra's concertmasters in 2008, the first woman to hold that position. In 2012, women still made up just 6% of the orchestra's membership. VPO president Clemens Hellsberg said the VPO now uses completely screened blind auditions.",  answer the following question. Note that the answer is present within the text.  Question: Who protested VPO?
Answer:
National Organization for Women and the International Alliance for Women in Music