diff --git a/book/source/04-certificates.md b/book/source/04-certificates.md
index 2f6f6ff..b00799d 100644
--- a/book/source/04-certificates.md
+++ b/book/source/04-certificates.md
@@ -592,7 +592,7 @@ To prevent accidental publication of these local User IDs (e.g. to public keyser
 Different mechanisms for discovering certificates, and updating certificate data exist in the OpenPGP space: 
 
 - A *Web Key Directory* service is operated by the entity that controls the domain name of the email in question. This means that WKD is decentralized, and the reliability of OpenPGP certificates may vary depending on the organization that operates a particular WKD instance.
-- The *keys.openpgp.org* service is a "verifying" keyserver: the keyserver software only published identity components (which include email addresses) after sending a verification email to that address, and receiving opt-in consent by the user of the email address. This service makes a different tradeoff: it is centralized, and relying on it to correctly perform the verification step requires trust in the operator. The tradeoff allows the service to only list identity information with the consent of the owner of that identity, and to prevent "enumeration" of the certificates and identities it stores (that is: third parties cannot obtain a list of email addresses in the service's database). By design, this service allows easy publication of revocations without requiring publication of any identity components.
+- The *keys.openpgp.org* service is a "verifying" keyserver: the keyserver software only publishes identity components (which include email addresses) after sending a verification email to that address, and receiving opt-in consent by the user of the email address. This service makes a different tradeoff: it is centralized, and relying on it to correctly perform the verification step requires trust in the operator. The tradeoff allows the service to only list identity information with the consent of the owner of that identity, and to prevent "enumeration" of the certificates and identities it stores (that is: third parties cannot obtain a list of email addresses in the service's database). By design, this service allows easy publication of revocations without requiring publication of any identity components.
 - *SKS-style keyservers* act as a distributed synchronizing database, which accepts certificate information without verification (TODO: does the network handle third party signatures? If so, how?[^hip1]).
 
 One central difference between hockeypuck and hagrid (the software that runs the *keys.openpgp.org* service) is that hockeypuck distributes identity packets and third-party certifications that have indeterminate validity, while hagrid does not.