diff --git a/Makefile b/Makefile
index d42f9b8c3..21096f893 100644
--- a/Makefile
+++ b/Makefile
@@ -131,7 +131,7 @@ endif
 endif
 
 libs :
-ifeq ($(CORE), UNKOWN)
+ifeq ($(CORE), UNKNOWN)
 	$(error OpenBLAS: Detecting CPU failed. Please set TARGET explicitly, e.g. make TARGET=your_cpu_target. Please read README for the detail.)
 endif
 ifeq ($(NOFORTRAN), 1)
diff --git a/cpuid_arm.c b/cpuid_arm.c
index 2f8959242..19aa90718 100644
--- a/cpuid_arm.c
+++ b/cpuid_arm.c
@@ -34,7 +34,7 @@
 #define CPU_CORTEXA15       	4
 
 static char *cpuname[] = {
-  "UNKOWN",
+  "UNKNOWN",
   "ARMV6",
   "ARMV7",
   "CORTEXA9",
diff --git a/cpuid_mips.c b/cpuid_mips.c
index c09902936..6f2932c94 100644
--- a/cpuid_mips.c
+++ b/cpuid_mips.c
@@ -75,7 +75,7 @@ USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 #define CPU_1004K	2
 
 static char *cpuname[] = {
-  "UNKOWN",
+  "UNKNOWN",
   "P5600",
   "1004K"
 };
diff --git a/cpuid_mips64.c b/cpuid_mips64.c
index dcb559a7c..0e32bfc0b 100644
--- a/cpuid_mips64.c
+++ b/cpuid_mips64.c
@@ -79,7 +79,7 @@ USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 #define CPU_I6500       6
 
 static char *cpuname[] = {
-  "UNKOWN",
+  "UNKNOWN",
   "SICORTEX",
   "LOONGSON3A",
   "LOONGSON3B",
diff --git a/cpuid_x86.c b/cpuid_x86.c
index 8e4a7cb84..eb986b6b6 100644
--- a/cpuid_x86.c
+++ b/cpuid_x86.c
@@ -1649,7 +1649,7 @@ static char *lowercpuname[] = {
 };
 
 static char *corename[] = {
-  "UNKOWN",
+  "UNKNOWN",
   "80486",
   "P5",
   "P6",