diff --git a/listings/features-default/tests/arithmetics_and_broadcasting.rs b/listings/features-default/tests/arithmetics_and_broadcasting.rs
index 2a5b412..f428245 100644
--- a/listings/features-default/tests/arithmetics_and_broadcasting.rs
+++ b/listings/features-default/tests/arithmetics_and_broadcasting.rs
@@ -20,8 +20,8 @@ fn example_basic_arithmetics() {
     // ANCHOR_END: basic_arithmetics_01
 
     // ANCHOR: basic_arithmetics_02
-    let mat = rt::arange(12).into_shape([3, 4]).into_owned();
-    let vec = rt::arange(4).into_shape([4]).into_owned();
+    let mat = rt::arange(12).into_shape([3, 4]);
+    let vec = rt::arange(4).into_shape([4]);
 
     // matrix multiplication
     let res = &mat % mat.t();
@@ -69,7 +69,7 @@ fn example_basic_arithmetics() {
 #[test]
 fn example_op_percent() {
     // ANCHOR: star_as_elem_mult
-    let mat = rt::arange(12).into_shape([3, 4]).into_owned();
+    let mat = rt::arange(12).into_shape([3, 4]);
     let vec = rt::arange(4);
 
     // element-wise matrix multiplication
@@ -135,9 +135,7 @@ fn example_lt_os_mp2() {
     // ANCHOR: lt_os_mp2_01
     // task definition
     let (naux, nocc, nvir) = (8, 2, 4); // subscripts (P, i, a)
-    let y = rt::arange(naux * nocc * nvir)
-        .into_shape([naux, nocc, nvir])
-        .into_owned();
+    let y = rt::arange(naux * nocc * nvir).into_shape([naux, nocc, nvir]);
     let ei = rt::arange(nocc);
     let ea = rt::arange(nvir);
     // ANCHOR_END: lt_os_mp2_01
@@ -167,11 +165,9 @@ fn example_ao2mo_vo() {
     // ANCHOR: ao2mo_vo_01
     // task definition
     let (naux, nocc, nvir, nao, _) = (8, 2, 4, 6, 6); // subscripts (P, i, a, μ, ν)
-    let y_ao = rt::arange(naux * nao * nao)
-        .into_shape([naux, nao, nao])
-        .into_owned();
-    let c_occ = rt::arange(nao * nocc).into_shape([nao, nocc]).into_owned();
-    let c_vir = rt::arange(nao * nvir).into_shape([nao, nvir]).into_owned();
+    let y_ao = rt::arange(naux * nao * nao).into_shape([naux, nao, nao]);
+    let c_occ = rt::arange(nao * nocc).into_shape([nao, nocc]);
+    let c_vir = rt::arange(nao * nvir).into_shape([nao, nvir]);
     // ANCHOR_END: ao2mo_vo_01
 
     // ANCHOR: ao2mo_vo_02
diff --git a/listings/features-default/tests/indexing.rs b/listings/features-default/tests/indexing.rs
index f650bd2..9d3c08a 100644
--- a/listings/features-default/tests/indexing.rs
+++ b/listings/features-default/tests/indexing.rs
@@ -4,7 +4,7 @@ use rstsr_core::prelude::*;
 fn example_index_by_num() {
     // ANCHOR: example_index_by_num_01
     // generate 3-D tensor A_ijk
-    let a = rt::arange(24).into_shape([4, 3, 2]).into_owned();
+    let a = rt::arange(24).into_shape([4, 3, 2]);
     println!("{:}", a);
 
     // B_jk = A_ijk where i = 2
@@ -39,7 +39,7 @@ fn example_index_by_num() {
 fn example_index_by_range() {
     // ANCHOR: example_index_by_range_01
     // generate 3-D tensor A_ijk
-    let a = rt::arange(24).into_shape([4, 3, 2]).into_owned();
+    let a = rt::arange(24).into_shape([4, 3, 2]);
     println!("{:}", a);
 
     // B_ijk = A_ijk where 1 <= i < 3
@@ -84,7 +84,7 @@ fn example_index_by_range() {
     // ANCHOR_END: example_index_by_range_04
 
     // ANCHOR: example_index_by_range_05
-    let a = rt::arange(24).into_shape([4, 3, 2]).into_owned();
+    let a = rt::arange(24).into_shape([4, 3, 2]);
     let b = a.slice((.., 1..3, ..2)); // equivalently `a.slice(s![.., 1..3, ..2])`
     println!("{:}", b);
     // output:
@@ -138,7 +138,7 @@ fn example_slice_with_strides() {
 #[test]
 fn example_insert_axes() {
     // ANCHOR: example_insert_axes_01
-    let a = rt::arange(24).into_shape([4, 3, 2]).into_owned();
+    let a = rt::arange(24).into_shape([4, 3, 2]);
 
     // insert new axis at the beginning
     let b = a.slice(NewAxis);
@@ -161,7 +161,7 @@ fn example_insert_axes() {
 #[should_panic]
 fn example_insert_axes_panic() {
     // ANCHOR: example_insert_axes_02
-    let a = rt::arange(24).into_shape([4, 3, 2]).into_owned();
+    let a = rt::arange(24).into_shape([4, 3, 2]);
 
     // insert new axis at the beginning
     let b = a.slice(Some(2));
@@ -173,7 +173,7 @@ fn example_insert_axes_panic() {
 #[test]
 fn example_ellipsis() {
     // ANCHOR: example_ellipsis_01
-    let a = rt::arange(24).into_shape([4, 3, 2]).into_owned();
+    let a = rt::arange(24).into_shape([4, 3, 2]);
 
     // using ellipsis to select index from last dimension
     // equivallently to `a.slice((.., .., 0))` for 3-D tensor
@@ -203,7 +203,7 @@ fn example_mixed_indexing() {
 #[test]
 fn example_elementwise_safe() {
     // ANCHOR: example_elementwise_safe
-    let a = rt::arange(24).into_shape([4, 3, 2]).into_owned();
+    let a = rt::arange(24).into_shape([4, 3, 2]);
 
     let val = a[[2, 2, 1]];
     println!("{:}", val);
@@ -234,7 +234,7 @@ fn example_elementwise_safe() {
 #[should_panic]
 fn example_elementwise_safe_panic() {
     // ANCHOR: example_elementwise_safe_panic
-    let a = rt::arange(24).into_shape([4, 3, 2]).into_owned();
+    let a = rt::arange(24).into_shape([4, 3, 2]);
 
     let val = a[[2, 2, 3]];
     println!("{:}", val);
@@ -245,7 +245,7 @@ fn example_elementwise_safe_panic() {
 #[test]
 fn example_elementwise_unchecked() {
     // ANCHOR: example_elementwise_unchecked
-    let a = rt::arange(24).into_shape([4, 3, 2]).into_owned();
+    let a = rt::arange(24).into_shape([4, 3, 2]);
 
     let val = unsafe { a.index_uncheck([2, 2, 1]) };
     println!("{:}", val);
@@ -256,7 +256,7 @@ fn example_elementwise_unchecked() {
 #[test]
 fn example_elementwise_unchecked_not_desired() {
     // ANCHOR: example_elementwise_unchecked_not_desired
-    let a = rt::arange(24).into_shape([4, 3, 2]).into_owned();
+    let a = rt::arange(24).into_shape([4, 3, 2]);
 
     let val = unsafe { a.index_uncheck([2, 2, 3]) };
     println!("{:}", val);
diff --git a/listings/features-default/tests/structure_and_ownership.rs b/listings/features-default/tests/structure_and_ownership.rs
index 478801f..f423dcb 100644
--- a/listings/features-default/tests/structure_and_ownership.rs
+++ b/listings/features-default/tests/structure_and_ownership.rs
@@ -7,12 +7,9 @@ fn example_tensor_ownership() {
     let tensor = rt::arange(12);
     let ptr_1 = tensor.rawvec().as_ptr();
 
-    // this will give cow tensor with 2-D shape
+    // this will give owned tensor with 2-D shape
     // since previous tensor is contiguous, this will not copy memory
-    let tensor = tensor.into_shape([3, 4]);
-
-    // convert cow tensor to owned tensor
-    let mut tensor = tensor.into_owned();
+    let mut tensor = tensor.into_shape([3, 4]);
     tensor += 1; // inplace operation
     let ptr_2 = tensor.rawvec().as_ptr();
 
@@ -83,7 +80,7 @@ fn example_to_scalar() {
 fn example_dim_conversion() {
     // ANCHOR: dim_conversion
     // fixed dimension
-    let a = rt::arange(12).into_shape([3, 4]).into_owned();
+    let a = rt::arange(12).into_shape([3, 4]);
     println!("{:?}", a);
     // output: 2-Dim, contiguous: Cc
 
@@ -99,7 +96,7 @@ fn example_dim_conversion() {
     // ANCHOR_END: dim_conversion
 
     // ANCHOR: dyn_dim_construct
-    let a = rt::arange(12).into_shape(vec![3, 4]).into_owned();
+    let a = rt::arange(12).into_shape(vec![3, 4]);
     println!("{:?}", a);
     // output: 2-Dim (dyn), contiguous: Cc
     // ANCHOR_END: dyn_dim_construct
diff --git a/listings/features-default/tests/tensor_creation.rs b/listings/features-default/tests/tensor_creation.rs
index 90a6156..0c6ce67 100644
--- a/listings/features-default/tests/tensor_creation.rs
+++ b/listings/features-default/tests/tensor_creation.rs
@@ -43,7 +43,7 @@ fn example_03() {
 
     // if you feel function `into_shape_assume_contig` ugly, following code also works
     let vec = vec![1, 2, 3, 4, 5, 6];
-    let tensor = rt::asarray(vec).into_shape([2, 3]).into_owned();
+    let tensor = rt::asarray(vec).into_shape([2, 3]);
     println!("{:}", tensor);
 
     // and even more concise
@@ -183,7 +183,7 @@ fn example_diag() {
     //  [ 0 2 0]
     //  [ 0 0 3]]
 
-    let tensor = rt::arange(9).into_shape([3, 3]).into_owned();
+    let tensor = rt::arange(9).into_shape([3, 3]);
     let diag = tensor.diag();
     println!("{:}", diag);
     // output: [ 0 4 8]