Merge pull request #63 from gfw-report/master

Add one AER'19 paper.

Author: NullHypothesis

references.bib

@@ -1,3 +1,14 @@
+@article{Chen2019a,
+	author = {Yuyu Chen and David Y. Yang},
+	title = {The Impact of Media Censorship: 1984 or {Brave New World}?},
+	journal = {American Economic Review},
+	volume = {109},
+	number = {6},
+	publisher = {American Economic Association},
+	year = {2019},
+	url = {https://pubs.aeaweb.org/doi/pdfplus/10.1257/aer.20171765},
+}
+
 @techreport{Ptacek1998a,
   author = {Thomas H. Ptacek and Timothy N. Newsham},
   title = {Insertion, Evasion, and Denial of Service: Eluding Network Intrusion Detection},