Reference: (Bibliography)bibliography [Catalogue] Wardwell, Allen. 1986. African Sculpture from the University Museum, University of Pennsylvania.|[Article] Coon, Carleton S. & Plass, Margaret B. 1957. African Sculpture: A Walk Through the Gallery. The University Museum Bulletin. 21 (4)|[Catalogue] Plass, Margaret B. 1956. African TribalSculpture.|[Journal] Hall, Henry U. "An Ivory Standing Cup From Benin" Vol.: Vol. XVII, No. 4.|[Catalogue, Exhibition] Curnow, Kathy. 2016. Iyare! Splendor and Tension In Benin's Palace Theatre.