diff --git a/book/source/03-cryptography.md b/book/source/03-cryptography.md
index 6e18837..797d9f2 100644
--- a/book/source/03-cryptography.md
+++ b/book/source/03-cryptography.md
@@ -32,12 +32,10 @@ A symmetric cryptographic key (which acts as a shared secret)
 
 Symmetric-key cryptography has major benefits: It is much faster than public-key cryptography (see below). Also, most current symmetric cryptographic algorithms are considered quantum-resistant[^postquantum].
 
-```{admonition} 
-:class: warning
-
-I am not convinced that this information is helpful but, if it remains, perhaps we need this additional statement: "That is, symmetric-key cryptographic mechanisms are currently considered to be resilient against known computer threats, providing a measure of assurance in the evolving landscape of cryptography and quantum computing."
-
 [^postquantum]: Daniel J. Bernstein (2009). ["Introduction to post-quantum cryptography" (PDF)](http://www.pqcrypto.org/www.springer.com/cda/content/document/cda_downloaddocument/9783540887010-c1.pdf) states that: "many important classes of cryptographic systems", including secret-key cryptographic mechanisms like AES "[..] are believed to resist classical computers and quantum computers." (pages 1, 2).
+
+```{warning} 
+I am not convinced that this information is helpful but, if it remains, perhaps we need this additional statement: "That is, symmetric-key cryptographic mechanisms are currently considered to be resilient against known computer threats, providing a measure of assurance in the evolving landscape of cryptography and quantum computing."
 ```
 
 However, exchanging the required shared secret is a problem that needs to be solved separately.
@@ -129,8 +127,7 @@ Digital signatures in OpenPGP are used in two primary contexts:
 
 OpenPGP uses a hybrid cryptosystem. [Hybrid cryptosystems](https://en.wikipedia.org/wiki/Hybrid_cryptosystem) combine the use of symmetric and asymmetric (public-key) cryptography to capitalize on the strengths of each, namely symmetric cryptography's speed and efficiency and public-key cryptography's mechanism for secure key exchange.
 
-```{admonition} 
-:class: warning
+```{warning} 
 
 Move this to the chapter that details it: