diff --git a/basic-geometry-test/basic-geometry-test.cbp b/basic-geometry-test/basic-geometry-test.cbp
index 40b18fd..c0dcc54 100644
--- a/basic-geometry-test/basic-geometry-test.cbp
+++ b/basic-geometry-test/basic-geometry-test.cbp
@@ -77,6 +77,10 @@
 			<Option compilerVar="CC" />
 		</Unit>
 		<Unit filename="tests/quaternion/quaternion_set_values.h" />
+		<Unit filename="tests/quaternion/quaternion_square_modulus.c">
+			<Option compilerVar="CC" />
+		</Unit>
+		<Unit filename="tests/quaternion/quaternion_square_modulus.h" />
 		<Unit filename="tests/quaternion/quaternion_swap.c">
 			<Option compilerVar="CC" />
 		</Unit>
diff --git a/basic-geometry-test/tests/quaternion/quaternion_is_zero.c b/basic-geometry-test/tests/quaternion/quaternion_is_zero.c
index 06375a6..3df943b 100644
--- a/basic-geometry-test/tests/quaternion/quaternion_is_zero.c
+++ b/basic-geometry-test/tests/quaternion/quaternion_is_zero.c
@@ -9,28 +9,28 @@ static const int _TEST_FP32_NONZERO_QUATERNION_AMOUNT = 11;
 
 static const BgcQuaternionFP32 _TEST_FP32_ZERO_QUATERNION_LIST[] = {
     { 0.0f, 0.0f, 0.0f, 0.0f },
-    { BGC_EPSYLON_FP32, 0.0f, 0.0f, 0.0f },
-    { -BGC_EPSYLON_FP32, 0.0f, 0.0f, 0.0f },
-    { 0.0f, BGC_EPSYLON_FP32, 0.0f, 0.0f },
-    { 0.0f, -BGC_EPSYLON_FP32, 0.0f, 0.0f },
-    { 0.0f, 0.0f, BGC_EPSYLON_FP32, 0.0f },
-    { 0.0f, 0.0f, -BGC_EPSYLON_FP32, 0.0f },
-    { 0.0f, 0.0f, 0.0f, BGC_EPSYLON_FP32 },
-    { 0.0f, 0.0f, 0.0f, -BGC_EPSYLON_FP32 }
+    { 0.75f * BGC_EPSYLON_FP32, 0.0f, 0.0f, 0.0f },
+    { -0.75f * BGC_EPSYLON_FP32, 0.0f, 0.0f, 0.0f },
+    { 0.0f, 0.75f * BGC_EPSYLON_FP32, 0.0f, 0.0f },
+    { 0.0f, -0.75f * BGC_EPSYLON_FP32, 0.0f, 0.0f },
+    { 0.0f, 0.0f, 0.75f * BGC_EPSYLON_FP32, 0.0f },
+    { 0.0f, 0.0f, -0.75f * BGC_EPSYLON_FP32, 0.0f },
+    { 0.0f, 0.0f, 0.0f, 0.75f * BGC_EPSYLON_FP32 },
+    { 0.0f, 0.0f, 0.0f, -0.75f * BGC_EPSYLON_FP32 }
 };
 
 static const BgcQuaternionFP32 _TEST_FP32_NONZERO_QUATERION_LIST[] = {
     { 0.0f, 1.0f, 0.0f, 0.0f },
-    { 1.5f * BGC_EPSYLON_FP32, 0.0f, 0.0f, 0.0f },
-    { -1.5f * BGC_EPSYLON_FP32, 0.0f, 0.0f, 0.0f },
-    { 0.0f, 1.5f * BGC_EPSYLON_FP32, 0.0f, 0.0f },
-    { 0.0f, -1.5f * BGC_EPSYLON_FP32, 0.0f, 0.0f },
-    { 0.0f, 0.0f, 1.5f * BGC_EPSYLON_FP32, 0.0f },
-    { 0.0f, 0.0f, -1.5f * BGC_EPSYLON_FP32, 0.0f },
-    { 0.0f, 0.0f, 0.0f, 1.5f * BGC_EPSYLON_FP32 },
-    { 0.0f, 0.0f, 0.0f, -1.5f * BGC_EPSYLON_FP32 },
-    { BGC_EPSYLON_FP32, BGC_EPSYLON_FP32, 0.0f, 0.0f },
-    { -BGC_EPSYLON_FP32, -BGC_EPSYLON_FP32, 0.0f, 0.0f }
+    { 1.25f * BGC_EPSYLON_FP32, 0.0f, 0.0f, 0.0f },
+    { -1.25f * BGC_EPSYLON_FP32, 0.0f, 0.0f, 0.0f },
+    { 0.0f, 1.25f * BGC_EPSYLON_FP32, 0.0f, 0.0f },
+    { 0.0f, -1.25f * BGC_EPSYLON_FP32, 0.0f, 0.0f },
+    { 0.0f, 0.0f, 1.25f * BGC_EPSYLON_FP32, 0.0f },
+    { 0.0f, 0.0f, -1.25f * BGC_EPSYLON_FP32, 0.0f },
+    { 0.0f, 0.0f, 0.0f, 1.25f * BGC_EPSYLON_FP32 },
+    { 0.0f, 0.0f, 0.0f, -1.25f * BGC_EPSYLON_FP32 },
+    { 1.25f * BGC_EPSYLON_FP32, 1.25f * BGC_EPSYLON_FP32, 0.0f, 0.0f },
+    { -1.25f * BGC_EPSYLON_FP32, -1.25f * BGC_EPSYLON_FP32, 0.0f, 0.0f }
 };
 
 int test_quaternion_is_zero_fp32()
@@ -65,28 +65,28 @@ static const int _TEST_FP64_NONZERO_QUATERNION_AMOUNT = 11;
 
 static const BgcQuaternionFP64 _TEST_FP64_ZERO_QUATERNION_LIST[] = {
     { 0.0, 0.0, 0.0, 0.0 },
-    { BGC_EPSYLON_FP64, 0.0, 0.0, 0.0 },
-    { -BGC_EPSYLON_FP64, 0.0, 0.0, 0.0 },
-    { 0.0, BGC_EPSYLON_FP64, 0.0, 0.0 },
-    { 0.0, -BGC_EPSYLON_FP64, 0.0, 0.0 },
-    { 0.0, 0.0, BGC_EPSYLON_FP64, 0.0 },
-    { 0.0, 0.0, -BGC_EPSYLON_FP64, 0.0 },
-    { 0.0, 0.0, 0.0, BGC_EPSYLON_FP64 },
-    { 0.0, 0.0, 0.0, -BGC_EPSYLON_FP64 }
+    { 0.75 * BGC_EPSYLON_FP64, 0.0, 0.0, 0.0 },
+    { -0.75 * BGC_EPSYLON_FP64, 0.0, 0.0, 0.0 },
+    { 0.0, 0.75 * BGC_EPSYLON_FP64, 0.0, 0.0 },
+    { 0.0, -0.75 * BGC_EPSYLON_FP64, 0.0, 0.0 },
+    { 0.0, 0.0, 0.75 * BGC_EPSYLON_FP64, 0.0 },
+    { 0.0, 0.0, -0.75 * BGC_EPSYLON_FP64, 0.0 },
+    { 0.0, 0.0, 0.0, 0.75 * BGC_EPSYLON_FP64 },
+    { 0.0, 0.0, 0.0, -0.75 * BGC_EPSYLON_FP64 }
 };
 
 static const BgcQuaternionFP64 _TEST_FP64_NONZERO_QUATERION_LIST[] = {
     { 0.0, 1.0, 0.0, 0.0 },
-    { 1.5 * BGC_EPSYLON_FP64, 0.0, 0.0, 0.0 },
-    { -1.5 * BGC_EPSYLON_FP64, 0.0, 0.0, 0.0 },
-    { 0.0, 1.5 * BGC_EPSYLON_FP64, 0.0, 0.0 },
-    { 0.0, -1.5 * BGC_EPSYLON_FP64, 0.0, 0.0 },
-    { 0.0, 0.0, 1.5 * BGC_EPSYLON_FP64, 0.0 },
-    { 0.0, 0.0, -1.5 * BGC_EPSYLON_FP64, 0.0 },
-    { 0.0, 0.0, 0.0, 1.5 * BGC_EPSYLON_FP64 },
-    { 0.0, 0.0, 0.0, -1.5 * BGC_EPSYLON_FP64 },
-    { BGC_EPSYLON_FP64, BGC_EPSYLON_FP64, 0.0, 0.0 },
-    { -BGC_EPSYLON_FP64, -BGC_EPSYLON_FP64, 0.0, 0.0 }
+    { 1.25 * BGC_EPSYLON_FP64, 0.0, 0.0, 0.0 },
+    { -1.25 * BGC_EPSYLON_FP64, 0.0, 0.0, 0.0 },
+    { 0.0, 1.25 * BGC_EPSYLON_FP64, 0.0, 0.0 },
+    { 0.0, -1.25 * BGC_EPSYLON_FP64, 0.0, 0.0 },
+    { 0.0, 0.0, 1.25 * BGC_EPSYLON_FP64, 0.0 },
+    { 0.0, 0.0, -1.25 * BGC_EPSYLON_FP64, 0.0 },
+    { 0.0, 0.0, 0.0, 1.25 * BGC_EPSYLON_FP64 },
+    { 0.0, 0.0, 0.0, -1.25 * BGC_EPSYLON_FP64 },
+    { 1.25 * BGC_EPSYLON_FP64, 1.25 * BGC_EPSYLON_FP64, 0.0, 0.0 },
+    { -1.25 * BGC_EPSYLON_FP64, -1.25 * BGC_EPSYLON_FP64, 0.0, 0.0 }
 };
 
 int test_quaternion_is_zero_fp64()
diff --git a/basic-geometry-test/tests/quaternion/quaternion_square_modulus.c b/basic-geometry-test/tests/quaternion/quaternion_square_modulus.c
new file mode 100644
index 0000000..364e893
--- /dev/null
+++ b/basic-geometry-test/tests/quaternion/quaternion_square_modulus.c
@@ -0,0 +1,34 @@
+#include "./quaternion_square_modulus.h"
+
+#include "./../../helpers.h"
+
+int test_quaternion_square_modulus_fp32()
+{
+    print_testing_name("bgc_quaternion_is_zero_fp32");
+
+    print_testing_success();
+
+    return TEST_SUCCES;
+}
+
+int test_quaternion_square_modulus_fp64()
+{
+    print_testing_name("bgc_quaternion_is_zero_fp64");
+
+    print_testing_success();
+
+    return TEST_SUCCES;
+}
+
+int test_quaternion_square_modulus()
+{
+    if (test_quaternion_square_modulus_fp32() != TEST_SUCCES) {
+        return TEST_FAILED;
+    }
+
+    if (test_quaternion_square_modulus_fp64() != TEST_SUCCES) {
+        return TEST_FAILED;
+    }
+
+    return TEST_SUCCES;
+}
diff --git a/basic-geometry-test/tests/quaternion/quaternion_square_modulus.h b/basic-geometry-test/tests/quaternion/quaternion_square_modulus.h
new file mode 100644
index 0000000..d5417fa
--- /dev/null
+++ b/basic-geometry-test/tests/quaternion/quaternion_square_modulus.h
@@ -0,0 +1,10 @@
+#ifndef _TEST_QUATERNION_SQUARE_MODULUS_H_
+#define _TEST_QUATERNION_SQUARE_MODULUS_H_
+
+int test_quaternion_square_modulus_fp32();
+
+int test_quaternion_square_modulus_fp64();
+
+int test_quaternion_square_modulus();
+
+#endif
diff --git a/basic-geometry-test/tests/utilities/is_unit.c b/basic-geometry-test/tests/utilities/is_unit.c
index 1d1433e..b6b1f53 100644
--- a/basic-geometry-test/tests/utilities/is_unit.c
+++ b/basic-geometry-test/tests/utilities/is_unit.c
@@ -9,15 +9,15 @@ static const int _TEST_FP32_NONUNIT_NUMBERS_AMOUNT = 4;
 
 static const float _TEST_FP32_UNIT_NUMBERS[] = {
     1.0f,
-    1.0f + BGC_EPSYLON_FP32,
-    1.0f - BGC_EPSYLON_FP32
+    1.0f + 0.75f * BGC_EPSYLON_FP32,
+    1.0f - 0.75f * BGC_EPSYLON_FP32
 };
 
 static const float _TEST_FP32_NONUNIT_NUMBERS[] = {
     0.0f,
     -1.0f,
-    1.0f + 2.0f * BGC_EPSYLON_FP32,
-    1.0f - 2.0f * BGC_EPSYLON_FP32
+    1.0f + 1.25f * BGC_EPSYLON_FP32,
+    1.0f - 1.25f * BGC_EPSYLON_FP32
 };
 
 int test_is_unit_fp32()
@@ -52,15 +52,15 @@ static const int _TEST_FP64_NONUNIT_NUMBERS_AMOUNT = 4;
 
 static const double _TEST_FP64_UNIT_NUMBERS[] = {
     1.0,
-    1.0 + BGC_EPSYLON_FP64,
-    1.0 - BGC_EPSYLON_FP64
+    1.0 + 0.75 * BGC_EPSYLON_FP64,
+    1.0 - 0.75 * BGC_EPSYLON_FP64
 };
 
 static const double _TEST_FP64_NONUNIT_NUMBERS[] = {
     0.0,
     -1.0,
-    1.0 + 2.0 * BGC_EPSYLON_FP64,
-    1.0 - 2.0 * BGC_EPSYLON_FP64
+    1.0 + 1.25 * BGC_EPSYLON_FP64,
+    1.0 - 1.25 * BGC_EPSYLON_FP64
 };
 
 int test_is_unit_fp64()
@@ -90,22 +90,20 @@ int test_is_unit_fp64()
 
 // ================ Square FP32 ================= //
 
-static const int _TEST_FP32_DATA_SQUARE_UNIT_AMOUNT = 5;
+static const int _TEST_FP32_DATA_SQUARE_UNIT_AMOUNT = 3;
 static const int _TEST_FP32_DATA_SQUARE_NONUNIT_AMOUNT = 4;
 
 static const float _TEST_FP32_DATA_SQUARE_UNIT[] = {
     1.0f,
-    1.0f + BGC_EPSYLON_FP32,
-    1.0f - BGC_EPSYLON_FP32,
-    1.0f + 2.0f * BGC_EPSYLON_FP32,
-    1.0f - 2.0f * BGC_EPSYLON_FP32
+    1.0f + 1.75f * BGC_EPSYLON_FP32,
+    1.0f - 1.75f * BGC_EPSYLON_FP32
 };
 
 static const float _TEST_FP32_DATA_SQUARE_NONUNIT[] = {
     0.0f,
     -1.0f,
-    1.0f + 2.5f * BGC_EPSYLON_FP32,
-    1.0f - 2.5f * BGC_EPSYLON_FP32
+    1.0f + 2.25f * BGC_EPSYLON_FP32,
+    1.0f - 2.25f * BGC_EPSYLON_FP32
 };
 
 int test_is_sqare_value_unit_fp32()
@@ -135,22 +133,20 @@ int test_is_sqare_value_unit_fp32()
 
 // ================ Square FP64 ================= //
 
-static const int _TEST_FP64_DATA_SQUARE_UNIT_AMOUNT = 5;
+static const int _TEST_FP64_DATA_SQUARE_UNIT_AMOUNT = 3;
 static const int _TEST_FP64_DATA_SQUARE_NONUNIT_AMOUNT = 4;
 
 static const double _TEST_FP64_DATA_SQUARE_UNIT[] = {
     1.0,
-    1.0 + BGC_EPSYLON_FP64,
-    1.0 - BGC_EPSYLON_FP64,
-    1.0 + 2.0 * BGC_EPSYLON_FP64,
-    1.0 - 2.0 * BGC_EPSYLON_FP64
+    1.0 + 1.75 * BGC_EPSYLON_FP64,
+    1.0 - 1.75 * BGC_EPSYLON_FP64
 };
 
 static const double _TEST_FP64_DATA_SQUARE_NONUNIT[] = {
     0.0,
     -1.0,
-    1.0 + 2.5 * BGC_EPSYLON_FP64,
-    1.0 - 2.5 * BGC_EPSYLON_FP64
+    1.0 + 2.25 * BGC_EPSYLON_FP64,
+    1.0 - 2.25 * BGC_EPSYLON_FP64
 };
 
 int test_is_sqare_value_unit_fp64()
diff --git a/basic-geometry-test/tests/utilities/is_zero.c b/basic-geometry-test/tests/utilities/is_zero.c
index aebbd39..eb2520b 100644
--- a/basic-geometry-test/tests/utilities/is_zero.c
+++ b/basic-geometry-test/tests/utilities/is_zero.c
@@ -4,22 +4,20 @@
 
 // ==================== FP32 ==================== //
 
-static const int _TEST_FP32_ZERO_NUMBERS_AMOUNT = 5;
+static const int _TEST_FP32_ZERO_NUMBERS_AMOUNT = 3;
 static const int _TEST_FP32_NONZERO_NUMBERS_AMOUNT = 4;
 
 static const float _TEST_FP32_ZERO_NUMBERS[] = {
     0.0f,
-    BGC_EPSYLON_FP32,
-    -BGC_EPSYLON_FP32,
-    BGC_SQUARE_EPSYLON_FP32,
-    -BGC_SQUARE_EPSYLON_FP32
+    0.75f * BGC_EPSYLON_FP32,
+    -0.75f * BGC_EPSYLON_FP32
 };
 
 static const float _TEST_FP32_NONZERO_NUMBERS[] = {
     1.0f,
     -1.0f,
-    (1.5f * BGC_EPSYLON_FP32),
-    -(1.5f * BGC_EPSYLON_FP32)
+    1.25f * BGC_EPSYLON_FP32,
+    -1.25f * BGC_EPSYLON_FP32
 };
 
 int test_is_zero_fp32()
@@ -49,22 +47,20 @@ int test_is_zero_fp32()
 
 // ==================== FP64 ==================== //
 
-static const int _TEST_FP64_ZERO_NUMBERS_AMOUNT = 5;
+static const int _TEST_FP64_ZERO_NUMBERS_AMOUNT = 3;
 static const int _TEST_FP64_NONZERO_NUMBERS_AMOUNT = 4;
 
 static const double _TEST_FP64_ZERO_NUMBERS[] = {
     0.0,
-    BGC_EPSYLON_FP64,
-    -BGC_EPSYLON_FP64,
-    BGC_SQUARE_EPSYLON_FP64,
-    -BGC_SQUARE_EPSYLON_FP64
+    0.75 * BGC_EPSYLON_FP64,
+    -0.75 * BGC_EPSYLON_FP64
 };
 
 static const double _TEST_FP64_NONZERO_NUMBERS[] = {
     1.0,
     -1.0,
-    (1.5 * BGC_EPSYLON_FP64),
-    -(1.5 * BGC_EPSYLON_FP64)
+    1.25 * BGC_EPSYLON_FP64,
+    -1.25 * BGC_EPSYLON_FP64
 };
 
 int test_is_zero_fp64()
diff --git a/basic-geometry-test/tests/vector2/vector2_is_zero.c b/basic-geometry-test/tests/vector2/vector2_is_zero.c
index 8201783..8d4770a 100644
--- a/basic-geometry-test/tests/vector2/vector2_is_zero.c
+++ b/basic-geometry-test/tests/vector2/vector2_is_zero.c
@@ -21,8 +21,8 @@ static const BgcVector2FP32 _TEST_FP32_NONZERO_VECTOR2_LIST[] = {
     { -1.25f * BGC_EPSYLON_FP32, 0.0f },
     { 0.0f, 1.25f * BGC_EPSYLON_FP32 },
     { 0.0f, -1.25f * BGC_EPSYLON_FP32 },
-    { BGC_EPSYLON_FP32, BGC_EPSYLON_FP32 },
-    { -BGC_EPSYLON_FP32, -BGC_EPSYLON_FP32 }
+    { 1.25f * BGC_EPSYLON_FP32, 1.25 * BGC_EPSYLON_FP32 },
+    { -1.25f * BGC_EPSYLON_FP32, -1.25f * BGC_EPSYLON_FP32 }
 };
 
 int test_vector2_is_zero_fp32()
diff --git a/basic-geometry-test/tests/versor/versor_is_identity.c b/basic-geometry-test/tests/versor/versor_is_identity.c
index a3cd901..d723210 100644
--- a/basic-geometry-test/tests/versor/versor_is_identity.c
+++ b/basic-geometry-test/tests/versor/versor_is_identity.c
@@ -9,14 +9,14 @@ static const int _TEST_FP32_NON_IDENTIYTY_VERSOR_AMOUNT = 5;
 
 static const BgcVersorFP32 _TEST_FP32_IDENTIYTY_VERSOR_LIST[] = {
     { 1.0f, 0.0f, 0.0f, 0.0f },
-    { 1.0f + BGC_EPSYLON_FP32, 0.0f, 0.0f, 0.0f },
-    { 1.0f - BGC_EPSYLON_FP32, 0.0f, 0.0f, 0.0f },
-    { 1.0f, BGC_EPSYLON_FP32, 0.0f, 0.0f },
-    { 1.0f, -BGC_EPSYLON_FP32, 0.0f, 0.0f },
-    { 1.0f, 0.0f, BGC_EPSYLON_FP32, 0.0f },
-    { 1.0f, 0.0f, -BGC_EPSYLON_FP32, 0.0f },
-    { 1.0f, 0.0f, 0.0f, BGC_EPSYLON_FP32 },
-    { 1.0f, 0.0f, 0.0f, -BGC_EPSYLON_FP32 }
+    { 1.0f + 0.75f * BGC_EPSYLON_FP32, 0.0f, 0.0f, 0.0f },
+    { 1.0f - 0.75f * BGC_EPSYLON_FP32, 0.0f, 0.0f, 0.0f },
+    { 1.0f, 0.75f * BGC_EPSYLON_FP32, 0.0f, 0.0f },
+    { 1.0f, -0.75f * BGC_EPSYLON_FP32, 0.0f, 0.0f },
+    { 1.0f, 0.0f, 0.75f * BGC_EPSYLON_FP32, 0.0f },
+    { 1.0f, 0.0f, -0.75f * BGC_EPSYLON_FP32, 0.0f },
+    { 1.0f, 0.0f, 0.0f, 0.75f * BGC_EPSYLON_FP32 },
+    { 1.0f, 0.0f, 0.0f, -0.75f * BGC_EPSYLON_FP32 }
 };
 
 static const BgcVersorFP32 _TEST_FP32_NON_IDENTIYTY_VERSOR_LIST[] = {
@@ -24,7 +24,7 @@ static const BgcVersorFP32 _TEST_FP32_NON_IDENTIYTY_VERSOR_LIST[] = {
     { 0.0f, 0.0f, 1.0f, 0.0f },
     { 0.0f, 0.0f, 0.0f, 1.0f },
     { 0.5f, 0.5f, 0.5f, 0.5f },
-    { 1.0f - 1.5f * BGC_EPSYLON_FP32, 0.0f, 0.0f, 0.0f }
+    { 1.0f - 1.25f * BGC_EPSYLON_FP32, 0.0f, 0.0f, 0.0f }
 };
 
 int test_versor_is_identity_fp32()
@@ -59,14 +59,14 @@ static const int _TEST_FP64_NON_IDENTIYTY_VERSOR_AMOUNT = 5;
 
 static const BgcVersorFP64 _TEST_FP64_IDENTIYTY_VERSOR_LIST[] = {
     { 1.0, 0.0, 0.0, 0.0 },
-    { 1.0 + BGC_EPSYLON_FP64, 0.0, 0.0, 0.0 },
-    { 1.0 - BGC_EPSYLON_FP64, 0.0, 0.0, 0.0 },
-    { 1.0, -BGC_EPSYLON_FP64, 0.0, 0.0 },
-    { 1.0, BGC_EPSYLON_FP64, 0.0, 0.0 },
-    { 1.0, 0.0, BGC_EPSYLON_FP64, 0.0 },
-    { 1.0, 0.0, -BGC_EPSYLON_FP64, 0.0 },
-    { 1.0, 0.0, 0.0, BGC_EPSYLON_FP64 },
-    { 1.0, 0.0, 0.0, -BGC_EPSYLON_FP64 }
+    { 1.0 + 0.75 * BGC_EPSYLON_FP64, 0.0, 0.0, 0.0 },
+    { 1.0 - 0.75 * BGC_EPSYLON_FP64, 0.0, 0.0, 0.0 },
+    { 1.0, -0.75 * BGC_EPSYLON_FP64, 0.0, 0.0 },
+    { 1.0, 0.75 * BGC_EPSYLON_FP64, 0.0, 0.0 },
+    { 1.0, 0.0, 0.75 * BGC_EPSYLON_FP64, 0.0 },
+    { 1.0, 0.0, -0.75 * BGC_EPSYLON_FP64, 0.0 },
+    { 1.0, 0.0, 0.0, 0.75 * BGC_EPSYLON_FP64 },
+    { 1.0, 0.0, 0.0, -0.75 * BGC_EPSYLON_FP64 }
 };
 
 static const BgcVersorFP64 _TEST_FP64_NON_IDENTIYTY_VERSOR_LIST[] = {
@@ -74,7 +74,7 @@ static const BgcVersorFP64 _TEST_FP64_NON_IDENTIYTY_VERSOR_LIST[] = {
     { 0.0, 0.0, 1.0, 0.0 },
     { 0.0, 0.0, 0.0, 1.0 },
     { 0.5, 0.5, 0.5, 0.5 },
-    { 1.0 - 1.5 * BGC_EPSYLON_FP64, 0.0, 0.0, 0.0 }
+    { 1.0 - 1.25 * BGC_EPSYLON_FP64, 0.0, 0.0, 0.0 }
 };
 
 int test_versor_is_identity_fp64()