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+Let's Encrypt: 
+Let's Encrypt is a Certificate Authority that provides free TLS certificates, making it easy for websites to enable HTTPS encryption and create a more secure Internet for everyone. Let's Encrypt is a project of the nonprofit Internet Security Research Group
+
+
+Internet Security Research Group:
+The Internet Security Research Group (ISRG) is a public-benefit non-profit corporation based in California which focuses on Internet security.
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