Multi-succedent sequent calculus for intuitionistic epistemic logic

A multi-succedent sequent calculus for intuitionistic epistemic logic (IEL) is introduced in the paper. It is proved that the structural rules of weakening and contraction and the rule of cut are admissible in the calculus. It is also proved that any sequent with at most one formula in succedent is derivable in the calculus, iff it is derivable in the standard non-multi-succedent sequent calculus of IEL.