diff --git a/berggren.jl b/berggren.jl
deleted file mode 100644
index 136ed95..0000000
--- a/berggren.jl
+++ /dev/null
@@ -1,18 +0,0 @@
-using SparseArrays
-include("ho_basis.jl")
-
-"Basis transformation from HO to momentum space"
-function get_W_matrix(basis_p, E_max, Λ, μ1ω1, μ2ω2=μ1ω1; weights=true)
-    Es, n1s, l1s, n2s, l2s = get_2p_basis(E_max, Λ)
-    W = zeros(ComplexF64, length(basis_p), length(Es))
-    Threads.@threads for idx in CartesianIndices(W)
-        (i1, i2) = Tuple(idx)
-        ((j1, j2), (k1, w1), (k2, w2)) = basis_p[i1]
-        if j1 == l1s[i2] && j2 == l2s[i2]
-            elem1 = 1/sqrt(sqrt(μ1ω1)) * (-1)^n1s[i2] * ho_basis(j1, n1s[i2], 1/sqrt(μ1ω1) * k1)
-            elem2 = 1/sqrt(sqrt(μ2ω2)) * (-1)^n2s[i2] * ho_basis(j2, n2s[i2], 1/sqrt(μ2ω2) * k2)
-            W[idx] = elem1 * elem2 * (weights ? w1 * w2 : 1)
-        end
-    end
-    return sparse(W)
-end
diff --git a/berggren_3body.jl b/berggren_3body.jl
index e4a3d9d..35a5439 100644
--- a/berggren_3body.jl
+++ b/berggren_3body.jl
@@ -1,7 +1,7 @@
 using LinearAlgebra, SparseArrays, Arpack
 include("helper.jl")
 include("p_space.jl")
-include("berggren.jl")
+include("ho_basis.jl")
 
 println("No of threads = ", Threads.nthreads())
 
diff --git a/berggren_3body_resonance.jl b/berggren_3body_resonance.jl
index 26d9bfb..bc2897c 100644
--- a/berggren_3body_resonance.jl
+++ b/berggren_3body_resonance.jl
@@ -1,7 +1,6 @@
 using LinearAlgebra, SparseArrays, Arpack
 include("helper.jl")
 include("p_space.jl")
-include("berggren.jl")
 
 println("No of threads = ", Threads.nthreads())
 atol = 10^-5
diff --git a/calculations/3body_Berggren_B2R_EC.jl b/calculations/3body_Berggren_B2R_EC.jl
index dd2a290..9824e42 100644
--- a/calculations/3body_Berggren_B2R_EC.jl
+++ b/calculations/3body_Berggren_B2R_EC.jl
@@ -2,7 +2,6 @@ using Arpack, SparseArrays, LRUCache
 using DelimitedFiles, Plots
 include("../ho_basis.jl")
 include("../p_space.jl")
-include("../berggren.jl")
 
 println("No of threads = ", Threads.nthreads())
 
diff --git a/calculations/3body_Berggren_R2R_EC.jl b/calculations/3body_Berggren_R2R_EC.jl
index bec0ae2..d147e4b 100644
--- a/calculations/3body_Berggren_R2R_EC.jl
+++ b/calculations/3body_Berggren_R2R_EC.jl
@@ -2,7 +2,6 @@ using Arpack, SparseArrays, LRUCache
 using DelimitedFiles, Plots
 include("../ho_basis.jl")
 include("../p_space.jl")
-include("../berggren.jl")
 
 println("No of threads = ", Threads.nthreads())
 
diff --git a/ho_basis.jl b/ho_basis.jl
index 63a0d3a..1ba55a8 100644
--- a/ho_basis.jl
+++ b/ho_basis.jl
@@ -204,4 +204,20 @@ function get_src_V12_matrix(V_of_r, E_max, Λ, μω_global; atol=10^-6, maxevals
     V12 =  U' * V_relative * U
 
     return V12
-end
\ No newline at end of file
+end
+
+"Basis transformation from HO to momentum space"
+function get_W_matrix(basis_p, E_max, Λ, μ1ω1, μ2ω2=μ1ω1; weights=true)
+    Es, n1s, l1s, n2s, l2s = get_2p_basis(E_max, Λ)
+    W = zeros(ComplexF64, length(basis_p), length(Es))
+    Threads.@threads for idx in CartesianIndices(W)
+        (i1, i2) = Tuple(idx)
+        ((j1, j2), (k1, w1), (k2, w2)) = basis_p[i1]
+        if j1 == l1s[i2] && j2 == l2s[i2]
+            elem1 = 1/sqrt(sqrt(μ1ω1)) * (-1)^n1s[i2] * ho_basis(j1, n1s[i2], 1/sqrt(μ1ω1) * k1)
+            elem2 = 1/sqrt(sqrt(μ2ω2)) * (-1)^n2s[i2] * ho_basis(j2, n2s[i2], 1/sqrt(μ2ω2) * k2)
+            W[idx] = elem1 * elem2 * (weights ? w1 * w2 : 1)
+        end
+    end
+    return sparse(W)
+end