diff --git a/src/GroupRings.jl b/src/GroupRings.jl
index e774052..c048048 100644
--- a/src/GroupRings.jl
+++ b/src/GroupRings.jl
@@ -254,8 +254,9 @@ end
 
 function groupring_mult(X::AbstractVector, Y::AbstractVector, pm::Array{Int,2})
    T = promote_type(eltype(X), eltype(Y))
-   result = zeros(T, X)
-   return groupring_mult!(X,Y,pm,result)
+   result = zeros(T, deepcopy(X))
+   groupring_mult!(X, Y, pm, result)
+   return result
 end
 
 function groupring_mult{T<:Number}(X::GroupRingElem{T}, Y::GroupRingElem{T})