diff --git a/docs/hazmat/primitives/aead.rst b/docs/hazmat/primitives/aead.rst
index b4e4eaf..3c45b52 100644
--- a/docs/hazmat/primitives/aead.rst
+++ b/docs/hazmat/primitives/aead.rst
@@ -231,4 +231,4 @@
             when the ciphertext has been changed, but will also occur when the
             key, nonce, or associated data are wrong.
 
-.. _`recommends a 96-bit IV length`: http://csrc.nist.gov/groups/ST/toolkit/BCM/documents/proposedmodes/gcm/gcm-spec.pdf
+.. _`recommends a 96-bit IV length`: https://csrc.nist.gov/publications/detail/sp/800-38d/final
diff --git a/docs/hazmat/primitives/asymmetric/ec.rst b/docs/hazmat/primitives/asymmetric/ec.rst
index 710c11c..6d02fdc 100644
--- a/docs/hazmat/primitives/asymmetric/ec.rst
+++ b/docs/hazmat/primitives/asymmetric/ec.rst
@@ -669,9 +669,9 @@
     ... )
 
 
-.. _`FIPS 186-3`: http://csrc.nist.gov/publications/fips/fips186-3/fips_186-3.pdf
+.. _`FIPS 186-3`: https://csrc.nist.gov/csrc/media/publications/fips/186/3/archive/2009-06-25/documents/fips_186-3.pdf
 .. _`FIPS 186-4`: http://nvlpubs.nist.gov/nistpubs/FIPS/NIST.FIPS.186-4.pdf
-.. _`800-56A`: http://csrc.nist.gov/publications/nistpubs/800-56A/SP800-56A_Revision1_Mar08-2007.pdf
+.. _`800-56A`: https://csrc.nist.gov/publications/detail/sp/800-56a/revised/archive/2007-03-14
 .. _`800-56Ar2`: http://nvlpubs.nist.gov/nistpubs/SpecialPublications/NIST.SP.800-56Ar2.pdf
 .. _`some concern`: https://crypto.stackexchange.com/questions/10263/should-we-trust-the-nist-recommended-ecc-parameters
 .. _`less than 224 bits`: http://www.ecrypt.eu.org/ecrypt2/documents/D.SPA.20.pdf
diff --git a/docs/hazmat/primitives/symmetric-encryption.rst b/docs/hazmat/primitives/symmetric-encryption.rst
index 9e27540..822c6a8 100644
--- a/docs/hazmat/primitives/symmetric-encryption.rst
+++ b/docs/hazmat/primitives/symmetric-encryption.rst
@@ -709,7 +709,7 @@
 
 
 .. _`described by Colin Percival`: http://www.daemonology.net/blog/2009-06-11-cryptographic-right-answers.html
-.. _`recommends a 96-bit IV length`: http://csrc.nist.gov/groups/ST/toolkit/BCM/documents/proposedmodes/gcm/gcm-spec.pdf
+.. _`recommends a 96-bit IV length`: https://csrc.nist.gov/publications/detail/sp/800-38d/final
 .. _`NIST SP-800-38D`: http://nvlpubs.nist.gov/nistpubs/Legacy/SP/nistspecialpublication800-38D.pdf
 .. _`Communications Security Establishment`: https://www.cse-cst.gc.ca
 .. _`encrypt`: https://ssd.eff.org/en/module/what-encryption