diff --git a/src/arithmetic.jl b/src/arithmetic.jl
index 07c59f2..a84e9c1 100644
--- a/src/arithmetic.jl
+++ b/src/arithmetic.jl
@@ -27,8 +27,6 @@ function mul!(result::GroupRingElem, X::GroupRingElem, Y::GroupRingElem)
     result = zero!(_dealias(result, X, Y))
     X_nzeros_idx = findall(!iszero, X.coeffs)
     Y_nzeros_idx = findall(!iszero, Y.coeffs)
-    # X_nzeros_idx = [i for i in eachindex(X.coeffs) if X[i] != zero(eltype(X))]
-    # Y_nzeros_idx = [i for i in eachindex(Y.coeffs) if Y[i] != zero(eltype(Y))]
 
     RG = parent(X)
 
diff --git a/src/ncring_interface.jl b/src/ncring_interface.jl
index f4f4bda..b355aed 100644
--- a/src/ncring_interface.jl
+++ b/src/ncring_interface.jl
@@ -7,7 +7,7 @@
 AbstractAlgebra.parent_type(::Type{GroupRingElem{T, GR}}) where {T, GR} = GR
 
 function AbstractAlgebra.elem_type(::Type{<:GroupRing{R,G,El}}) where {R,G,El}
-	return GroupRingElem{elem_type(R), GroupRing{R,G,El}}
+    return GroupRingElem{elem_type(R), GroupRing{R,G,El}}
 end
 
 AbstractAlgebra.base_ring(RG::GroupRing) = RG.base_ring
@@ -18,11 +18,11 @@ AbstractAlgebra.isexact_type(::Type{<:GroupRingElem{T}}) where T = isexact_type(
 
 # hash(GroupRingElem) = 0x839279ac6f12f62a
 function Base.hash(X::GroupRingElem, h::UInt)
-   return ⊻(hash(X.coeffs, h), hash(parent(X), h), 0x839279ac6f12f62a)
+    return ⊻(hash(X.coeffs, h), hash(parent(X), h), 0x839279ac6f12f62a)
 end
 
 function Base.deepcopy_internal(X::GroupRingElem, dict::IdDict)
-   return parent(X)(deepcopy(X.coeffs))
+    return parent(X)(deepcopy(X.coeffs))
 end
 
 Base.zero(RG::GroupRing) = RG(0)
@@ -30,7 +30,7 @@ Base.one(RG::GroupRing) = RG(1)
 Base.iszero(X::GroupRingElem{T}) where T = all(x == zero(T) for x in X.coeffs.nzval)
 
 function Base.isone(X::GroupRingElem{T}) where T
-	idx = _identity_idx(parent(X))
+    idx = _identity_idx(parent(X))
     X[idx] == one(T) || return false
     all(X[i] == zero(T) for i in eachindex(X.coeffs) if i != idx) || return false
     return true
@@ -43,33 +43,33 @@ end
 ###############################################################################
 
 Base.show(io::IO, RG::GroupRing) =
-   print(io, "Group ring of $(RG.group) with coefficients in $(base_ring(RG))")
+print(io, "Group ring of $(RG.group) with coefficients in $(base_ring(RG))")
 
 function Base.show(io::IO, X::GroupRingElem{T}) where T
-   RG = parent(X)
-   if iszero(X)
-      print(io, "$(zero(T))*$(multiplicative_id(RG.group))")
-   elseif hasbasis(RG)
-      suppX = supp(X)
-      elts = String[]
+    RG = parent(X)
+    if iszero(X)
+        print(io, "$(zero(T))*$(multiplicative_id(RG.group))")
+    elseif hasbasis(RG)
+        suppX = supp(X)
+        elts = String[]
 
-      elts = String[]
-      sgn = ""
-      for g in suppX
-         coeff = X[g]
-         if X[g] < 0
-            sgn = " - "
-            coeff = -coeff
-         end
-	      push!(elts, sgn*string(coeff)*string(g))
-         sgn = " + "
-      end
-      str = join(elts, "")
-      print(io, str)
-   else
-      @warn("Basis of the parent group ring is not defined, showing coeffs")
-      show(io, MIME("text/plain"), X.coeffs)
-   end
+        elts = String[]
+        sgn = ""
+        for g in suppX
+            coeff = X[g]
+            if X[g] < 0
+                sgn = " - "
+                coeff = -coeff
+            end
+            push!(elts, sgn*string(coeff)*string(g))
+            sgn = " + "
+        end
+        str = join(elts, "")
+        print(io, str)
+    else
+        @warn("Basis of the parent group ring is not defined, showing coeffs")
+        show(io, MIME("text/plain"), X.coeffs)
+    end
 end
 
 AbstractAlgebra.needs_parentheses(X::GroupRingElem) = true
@@ -83,42 +83,42 @@ AbstractAlgebra.show_minus_one(::Type{<:GroupRingElem}) = true
 ###############################################################################
 
 function ==(X::GroupRingElem{T}, Y::GroupRingElem{S}) where {T,S}
-   if promote_type(T,S) ≠ T || promote_type(T,S) ≠ S
-      @warn "Comparing elements with incompatible coeffs Rings: $T and $S can be only compared as $(promote_type(T,S))"
-   end
-   length(X.coeffs) == length(Y.coeffs) || return false
-   parent(X).group == parent(Y).group || return false
-   return all(x == y for (x,y) in zip(X.coeffs, Y.coeffs))
+    if promote_type(T,S) ≠ T || promote_type(T,S) ≠ S
+        @warn "Comparing elements with incompatible coeffs Rings: $T and $S can be only compared as $(promote_type(T,S))"
+    end
+    length(X.coeffs) == length(Y.coeffs) || return false
+    parent(X).group == parent(Y).group || return false
+    return all(x == y for (x,y) in zip(X.coeffs, Y.coeffs))
 end
 
 Base.isequal(X::GroupRingElem, Y::GroupRingElem) = X == Y
 
-_equalorzero(x,y) = x == y || x == 0 || y == 0
+_equalorzero(x,y) = x == 0 || y == 0 || x == y
 
 function ==(A::GroupRing, B::GroupRing)
-   A.group == B.group || return false
-   # base_ring(A) == base_ring(B) || return false
+    A.group == B.group || return false
+    # base_ring(A) == base_ring(B) || return false
 
-   bases = hasbasis(A) && hasbasis(B)
-   caches = cachesmultiplication(A) && cachesmultiplication(B)
+    bases = hasbasis(A) && hasbasis(B)
+    caches = cachesmultiplication(A) && cachesmultiplication(B)
 
-   if bases && caches
-      length(A) == length(B) || return false
-      size(A.pm) == size(B.pm) || return false
-      all(A.basis[i] == B.basis[i] for i in eachindex(A.basis)) || return false
-      all(_equalorzero(A.pm[i], B.pm[i]) for i in eachindex(A.pm)) || return false
-      return true
-   elseif bases # && !caches
-      length(A) == length(B) || return false
-      all(A.basis[i] == B.basis[i] for i in eachindex(A.basis)) || return false
-      return true
-   elseif caches # && !bases
-      size(A.pm) == size(B.pm) || return false
-      all(A.pm[i] == B.pm[i] for i in eachindex(A.pm)) || return false
-      return true
-   else
-      return false
-   end
+    if bases && caches
+        length(A) == length(B) || return false
+        size(A.pm) == size(B.pm) || return false
+        all(A.basis[i] == B.basis[i] for i = eachindex(A.basis)) || return false
+        all(_equalorzero(A.pm[i], B.pm[i]) for i=eachindex(A.pm)) || return false
+        return true
+    elseif bases # && !caches
+        length(A) == length(B) || return false
+        all(A.basis[i] == B.basis[i] for i in eachindex(A.basis)) || return false
+        return true
+    elseif caches # && !bases
+        size(A.pm) == size(B.pm) || return false
+        all(A.pm[i] == B.pm[i] for i in eachindex(A.pm)) || return false
+        return true
+    else
+        return false
+    end
 end
 
 ###############################################################################
@@ -128,13 +128,13 @@ end
 ###############################################################################
 
 function AbstractAlgebra.divexact_left(X::GroupRingElem, Y::GroupRingElem)
-   isunit(Y) || throw(DivideError())
-   return inv(Y)*X
+    isunit(Y) || throw(DivideError())
+    return inv(Y)*X
 end
 
 function AbstractAlgebra.divexact_right(X::GroupRingElem, Y::GroupRingElem)
-   isunit(Y) || throw(DivideError())
-   return X*inv(Y)
+    isunit(Y) || throw(DivideError())
+    return X*inv(Y)
 end
 
 ###############################################################################
@@ -161,24 +161,25 @@ function AbstractAlgebra.promote_rule(u::Type{U}, x::Type{GREl}) where {T, GREl<
     return AbstractAlgebra.promote_rule(x, u)
 end
 
+
 function Base.rand(RG::GroupRing, density=0.05, args...)
-	l = length(RG)
+    l = length(RG)
 
-	if cachesmultiplication(RG)
-		nzind = rand(1:size(RG.pm, 1), floor(Int, density*l))
-	else
-		nzind = rand(1:l, floor(Int, density*l))
-	end
+    if cachesmultiplication(RG)
+        nzind = rand(1:size(RG.pm, 1), floor(Int, density*l))
+    else
+        nzind = rand(1:l, floor(Int, density*l))
+    end
 
-   nzval = [rand(base_ring(RG), args...) for _ in nzind]
+    nzval = [rand(base_ring(RG), args...) for _ in nzind]
 
-	return GroupRingElem(sparsevec(nzind, nzval, l), RG)
+    return GroupRingElem(sparsevec(nzind, nzval, l), RG)
 end
 
 function Base.isapprox(X::GroupRingElem{T}, Y::GroupRingElem{S};
-	atol::Real=sqrt(eps())) where {T,S}
-   parent(X) == parent(Y) || return false
-   return isapprox(X.coeffs, Y.coeffs, atol=atol)
+    atol::Real=sqrt(eps())) where {T,S}
+    parent(X) == parent(Y) || return false
+    return isapprox(X.coeffs, Y.coeffs, atol=atol)
 end
 
 Base.isapprox(X::GroupRingElem{T}, a::T; atol::Real=sqrt(eps())) where T = isapprox(X, RG(a))
@@ -192,6 +193,6 @@ Base.isapprox(a::T, X::GroupRingElem{T}; atol::Real=sqrt(eps())) where T = isapp
 ###############################################################################
 
 function AbstractAlgebra.isunit(X::GroupRingElem)
-   count(!iszero, X.coeffs) == 1 || return false
-   return isunit(X[supp(X)[1]])
+    count(!iszero, X.coeffs) == 1 || return false
+    return isunit(X[supp(X)[1]])
 end