diff --git a/Gemfile.lock b/Gemfile.lock
index 30644ff..4090d4f 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -1,8 +1,8 @@
 GEM
   remote: https://rubygems.org/
   specs:
-    addressable (2.7.0)
-      public_suffix (>= 2.0.2, < 5.0)
+    addressable (2.8.1)
+      public_suffix (>= 2.0.2, < 6.0)
     asciidoctor (2.0.10)
     asciimath (1.0.9)
     bibtex-ruby (5.1.4)
@@ -193,7 +193,7 @@ GEM
     nokogiri (1.10.9)
       mini_portile2 (~> 2.4.0)
     optout (0.0.2)
-    public_suffix (4.0.5)
+    public_suffix (5.0.0)
     rake (12.3.3)
     rchardet (1.8.0)
     relaton (1.1.0)