diff --git a/src/JuliaFEM.jl b/src/JuliaFEM.jl
index 47d6471..418cc04 100644
--- a/src/JuliaFEM.jl
+++ b/src/JuliaFEM.jl
@@ -60,7 +60,7 @@ include("integrate.jl")  # default integration points for elements
 export get_integration_points
 
 include("sparse.jl")
-export add!, SparseMatrixCOO, get_nonzero_rows, get_nonzero_columns
+export add!, SparseMatrixCOO, SparseVectorCOO, get_nonzero_rows, get_nonzero_columns
 
 include("problems.jl") # common problem routines
 export Problem, AbstractProblem, FieldProblem, BoundaryProblem,
diff --git a/src/sparse.jl b/src/sparse.jl
index 48c466d..a93e990 100644
--- a/src/sparse.jl
+++ b/src/sparse.jl
@@ -10,8 +10,14 @@ type SparseMatrixCOO{T<:Real}
     V :: Vector{T}
 end
 
+typealias SparseVectorCOO SparseMatrixCOO
+
 function SparseMatrixCOO()
-    SparseMatrixCOO{Float64}([], [], [])
+    return SparseMatrixCOO{Float64}([], [], [])
+end
+
+function SparseVectorCOO(I::Vector, V::Vector)
+    return SparseVectorCOO(I, ones(I), V)
 end
 
 function convert(::Type{SparseMatrixCOO}, A::SparseMatrixCSC)
@@ -132,7 +138,15 @@ function add!(A::SparseMatrixCOO, dofs::Vector{Int}, data::Array{Float64}, dim::
     append!(A.V, vec(data))
 end
 
-""" Combine (I,J,V) values is possible to reduce memory usage. """
+""" Add SparseVector to SparseVectorCOO. """
+function add!(a::SparseVectorCOO, b::SparseVector)
+    I, V = findnz(b)
+    c = SparseVectorCOO(I, V)
+    append!(a, c)
+    return
+end
+
+""" Combine (I,J,V) values if possible to reduce memory usage. """
 function optimize!(A::SparseMatrixCOO)
     I, J, V = findnz(sparse(A))
     A.I = I
diff --git a/test/test_interfaces.jl b/test/test_interfaces.jl
deleted file mode 100644
index cee9355..0000000
--- a/test/test_interfaces.jl
+++ /dev/null
@@ -1,12 +0,0 @@
-# This file is a part of JuliaFEM.
-# License is MIT: see https://github.com/JuliaFEM/JuliaFEM.jl/blob/master/LICENSE.md
-
-module InterfaceTests
-
-using JuliaFEM.Testing
-
-function test_foo()
-    @test 1+2 == 3
-end
-
-end
diff --git a/test/test_sparse.jl b/test/test_sparse.jl
new file mode 100644
index 0000000..bdf4515
--- /dev/null
+++ b/test/test_sparse.jl
@@ -0,0 +1,19 @@
+# This file is a part of JuliaFEM.
+# License is MIT: see https://github.com/JuliaFEM/JuliaFEM.jl/blob/master/LICENSE.md
+
+using JuliaFEM
+using JuliaFEM.Testing
+
+@testset "Add to SparseMatrixCOO" begin
+    A = SparseMatrixCOO()
+    A2 = reshape(collect(1:9), 3, 3)
+    add!(A, sparse(A2))
+    @test isapprox(full(A), full(A2))
+end
+
+@testset "Add to SparseVectorCOO" begin
+    b = SparseVectorCOO()
+    b2 = collect(1:3)
+    add!(b, sparse(b2))
+    @test isapprox(full(b), full(b2))
+end