6.1 Normative References

[ChaCha] Bernstein, D., "ChaCha, a variant of Salsa20", January 2008, <http://cr.yp.to/chacha/chacha-20080128.pdf>.
[Poly1305] Bernstein, D., "The Poly1305-AES message-authentication code", March 2005, <http://cr.yp.to/mac/poly1305-20050329.pdf>.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, March 1997, <https://www.rfc-editor.org/info/rfc2119>.
[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, May 2017, <https://www.rfc-editor.org/info/rfc8174>.