diff --git a/yubikey-ssh-pkcs11.md b/yubikey-ssh-pkcs11.md
index 5ee35dc..4b462ec 100644
--- a/yubikey-ssh-pkcs11.md
+++ b/yubikey-ssh-pkcs11.md
@@ -9,7 +9,7 @@ ssh -I /Library/OpenSC/lib/opensc-pkcs11.so root@example.com
 ```
 alias ssh-keygeni='ssh-keygen -D /Library/OpenSC/lib/opensc-pkcs11.so'
 alias sshi='ssh -I /Library/OpenSC/lib/opensc-pkcs11.so root@example.com'
-alias sshif='ssh -o 'ForwardAgent yes' -I /Library/OpenSC/lib/opensc-pkcs11.so root@example.com'
+alias sshif='ssh -o "ForwardAgent yes" -I /Library/OpenSC/lib/opensc-pkcs11.so root@example.com'
 ```
 
 `~/.ssh/config`