diff --git a/Gemfile b/Gemfile
index dc27977..89f3bd5 100644
--- a/Gemfile
+++ b/Gemfile
@@ -4,5 +4,4 @@ ruby "2.5.1"
 gem "nokogiri"
 gem "jekyll"
 gem "jekyll-scholar", group: :jekyll_plugins
-gem "kramdown", ">= 2.3.1"
 
diff --git a/Gemfile.lock b/Gemfile.lock
index 634b42e..510e352 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -3,42 +3,65 @@ GEM
   specs:
     addressable (2.8.0)
       public_suffix (>= 2.0.2, < 5.0)
+    bibtex-ruby (6.0.0)
+      latex-decode (~> 0.0)
+    citeproc (1.0.10)
+      namae (~> 1.0)
+    citeproc-ruby (1.1.14)
+      citeproc (~> 1.0, >= 1.0.9)
+      csl (~> 1.6)
     colorator (1.1.0)
-    concurrent-ruby (1.1.5)
-    em-websocket (0.5.1)
+    concurrent-ruby (1.1.9)
+    csl (1.6.0)
+      namae (~> 1.0)
+      rexml
+    csl-styles (1.0.1.11)
+      csl (~> 1.0)
+    em-websocket (0.5.3)
       eventmachine (>= 0.12.9)
-      http_parser.rb (~> 0.6.0)
+      http_parser.rb (~> 0)
     eventmachine (1.2.7)
-    ffi (1.11.1)
+    ffi (1.15.4)
     forwardable-extended (2.6.0)
-    http_parser.rb (0.6.0)
-    i18n (0.9.5)
+    http_parser.rb (0.8.0)
+    i18n (1.8.11)
       concurrent-ruby (~> 1.0)
-    jekyll (3.8.6)
+    jekyll (4.2.1)
       addressable (~> 2.4)
       colorator (~> 1.0)
       em-websocket (~> 0.5)
-      i18n (~> 0.7)
-      jekyll-sass-converter (~> 1.0)
+      i18n (~> 1.0)
+      jekyll-sass-converter (~> 2.0)
       jekyll-watch (~> 2.0)
-      kramdown (~> 1.14)
+      kramdown (~> 2.3)
+      kramdown-parser-gfm (~> 1.0)
       liquid (~> 4.0)
-      mercenary (~> 0.3.3)
+      mercenary (~> 0.4.0)
       pathutil (~> 0.9)
-      rouge (>= 1.7, < 4)
+      rouge (~> 3.0)
       safe_yaml (~> 1.0)
-    jekyll-sass-converter (1.5.2)
-      sass (~> 3.4)
+      terminal-table (~> 2.0)
+    jekyll-sass-converter (2.1.0)
+      sassc (> 2.0.1, < 3.0)
+    jekyll-scholar (7.0.0)
+      bibtex-ruby (~> 6.0)
+      citeproc-ruby (~> 1.0)
+      csl-styles (~> 1.0)
+      jekyll (~> 4.0)
     jekyll-watch (2.2.1)
       listen (~> 3.0)
-    kramdown (1.17.0)
+    kramdown (2.3.1)
+      rexml
+    kramdown-parser-gfm (1.1.0)
+      kramdown (~> 2.0)
+    latex-decode (0.3.2)
     liquid (4.0.3)
-    listen (3.1.5)
-      rb-fsevent (~> 0.9, >= 0.9.4)
-      rb-inotify (~> 0.9, >= 0.9.7)
-      ruby_dep (~> 1.2)
-    mercenary (0.3.6)
+    listen (3.7.0)
+      rb-fsevent (~> 0.10, >= 0.10.3)
+      rb-inotify (~> 0.9, >= 0.9.10)
+    mercenary (0.4.0)
     mini_portile2 (2.6.1)
+    namae (1.1.1)
     nokogiri (1.12.5)
       mini_portile2 (~> 2.6.1)
       racc (~> 1.4)
@@ -46,23 +69,24 @@ GEM
       forwardable-extended (~> 2.6)
     public_suffix (4.0.6)
     racc (1.5.2)
-    rb-fsevent (0.10.3)
-    rb-inotify (0.10.0)
+    rb-fsevent (0.11.0)
+    rb-inotify (0.10.1)
       ffi (~> 1.0)
-    rouge (3.7.0)
-    ruby_dep (1.5.0)
+    rexml (3.2.5)
+    rouge (3.26.1)
     safe_yaml (1.0.5)
-    sass (3.7.4)
-      sass-listen (~> 4.0.0)
-    sass-listen (4.0.0)
-      rb-fsevent (~> 0.9, >= 0.9.4)
-      rb-inotify (~> 0.9, >= 0.9.7)
+    sassc (2.4.0)
+      ffi (~> 1.9)
+    terminal-table (2.0.0)
+      unicode-display_width (~> 1.1, >= 1.1.1)
+    unicode-display_width (1.8.0)
 
 PLATFORMS
   ruby
 
 DEPENDENCIES
   jekyll
+  jekyll-scholar
   nokogiri
 
 RUBY VERSION