fix missing quote and add hush halving citation

sietch.bib

@@ -39,6 +39,13 @@
     author={Hush},
     title={Old Hush Block Explorer},
     url={https://hushold.explorer.dexstats.info/block/0003a67bc26fe564b75daf11186d360652eb435a35ba3d9d3e7e5d5f8e62dc17},
+    urldate={2020-05-24}
+}
+
+@misc{HushHalving,
+    author={Hush Developers},
+    title={Hush Halving Countdown},
+    url={https://myhush.org/halving},
    urldate={2020-05-24}
 }
 

sietch.tex

@@ -696,7 +696,7 @@ There are advanced forms of Value Analysis such as \textbf{Danaan-Gift Attacks},
 0.72345618 and see if a $ z \rightarrow t $ transaction happens which has all or most of these particular values, perhaps modified by a default transaction fee. This attack does not have a high probabilty of working in any one circumstance, but it's like effective to "do on repeat", as nothing stops the attacker from trying again and again.
 
 \Hush will sidestep most value analysis by disabling transparent outputs
-in late November of 2020 and become a "privacy by default blockchain.
+in late November of 2020 and become a "privacy by default" blockchain at block 340,000 \cite{HushHalving}.
 
 \nsubsection{Fee Analysis}