diff --git a/src/crypto/elliptic/p256_asm_s390x.s b/src/crypto/elliptic/p256_asm_s390x.s
index c5b55a04c3..cf37e204c7 100644
--- a/src/crypto/elliptic/p256_asm_s390x.s
+++ b/src/crypto/elliptic/p256_asm_s390x.s
@@ -2465,7 +2465,7 @@ TEXT ·p256PointDoubleAsm(SB), NOSPLIT, $0
 #define PL    V30
 #define PH    V31
 /*
- * https://choucroutage.com/Papers/SideChannelAttacks/ctrsa-2011-brown.pdf "Software Implementation of the NIST Elliptic Curves Over Prime Fields"
+ * https://delta.cs.cinvestav.mx/~francisco/arith/julio.pdf "Software Implementation of the NIST Elliptic Curves Over Prime Fields"
  *
  * A = X₁×Z₂²
  * B = Y₁×Z₂³
diff --git a/src/runtime/write_err_android.go b/src/runtime/write_err_android.go
index bf99b5f6c5..2419fc8663 100644
--- a/src/runtime/write_err_android.go
+++ b/src/runtime/write_err_android.go
@@ -21,7 +21,7 @@ var (
 // in kernel ring buffers. In Android-L, those /dev/log files are no longer
 // accessible and logging is done through a centralized user-mode logger, logd.
 //
-// https://android.googlesource.com/platform/system/core/+/master/liblog/logd_write.c
+// https://android.googlesource.com/platform/system/core/+/refs/tags/android-6.0.1_r78/liblog/logd_write.c
 type loggerType int32
 
 const (