Elliptic Families of Solutions of the Kadomtsev-Petviashvili Equation   and the Field Elliptic Calogero-Moser System
  We present the Lax pair for the field elliptic Calogero-Moser system and establish a connection between this system and the Kadomtsev-Petviashvili equation. Namely, we consider elliptic families of solutions of the KP equation, such that their poles satisfy a constraint of being balanced. We show that the dynamics of these poles is described by a reduction of the field elliptic CM system.   We construct a wide class of solutions to the field elliptic CM system by showing that any N-fold branched cover of an elliptic curve gives rise to an elliptic family of solutions of the KP equation with balanced poles. 
A. Akhmetshin, I. Krichever, Yu. Volvovski