Duality transformation formulas for multiple elliptic hypergeometric   series of type $BC$
  New duality transformation formulas are proposed for multiple elliptic hypergeometric series of type $BC$ and of type $C$. Various transformation and summation formulas are derived as special cases to recover some previously known results. 
Yasushi Komori, Yasuho Masuda, Masatoshi Noumi
math.CA