diff --git a/internal/oid/oid.go b/internal/oid/oid.go
index 7910088..262c504 100644
--- a/internal/oid/oid.go
+++ b/internal/oid/oid.go
@@ -86,9 +86,9 @@ var SigningCertificate = asn1.ObjectIdentifier{1, 2, 840, 113549, 1, 9, 16, 2, 1
 // Reference: https://datatracker.ietf.org/doc/html/rfc5035#section-3
 var SigningCertificateV2 = asn1.ObjectIdentifier{1, 2, 840, 113549, 1, 9, 16, 2, 47}
 
-// ExtKeyUsage (id-ce-extKeyUsage) is defined in RFC 2459
+// ExtKeyUsage (id-ce-extKeyUsage) is defined in RFC 5280
 //
-// Reference: https://datatracker.ietf.org/doc/html/rfc2459#appendix-B.2
+// Reference: https://www.rfc-editor.org/rfc/rfc5280.html#section-4.2.1.12
 var ExtKeyUsage = asn1.ObjectIdentifier{2, 5, 29, 37}
 
 // TimeStamping (id-kp-timeStamping) is defined in RFC 3161 2.3